Khwarizm was an important centre of learning in Central Asia, providing Al-Biruni access to excellent teachers, scientific knowledge, languages, and philosophical traditions. This strong educational foundation later enabled his studies of India. Therefore, Option D is correct. The other options contradict the cosmopolitan intellectual environment of Khwarizm.

Al-Biruni was familiar with Greek thinkers such as Plato and Aristotle despite not knowing Greek. This was possible because many Greek works had already been translated into Arabic. Therefore, both the Assertion and Reason are true, and the Reason directly explains how Al-Biruni acquired this knowledge.

In 1017, Sultan Mahmud of Ghazni invaded Khwarizm. Following this conquest, Al-Biruni was taken to Ghazni as a hostage. His stay there later enabled extensive interaction with Indian society and culture. Therefore, Option B correctly identifies the region involved.

Punjab's annexation gave Al-Biruni contact with local Indian populations (c). His stay as a hostage led him to develop affection for Ghazni (d). Studying with Brahmana scholars helped him learn Sanskrit (a). Translation activities facilitated the exchange of ideas across cultures (b). Therefore, Option C is correct.

Al-Biruni admired Sanskrit but noted its vast vocabulary and numerous inflections. He compared its complexity to Arabic. Despite the difficulty, he mastered the language through dedicated study. Therefore, Option A accurately reflects his observations regarding Sanskrit.

Al-Biruni extensively studied important Sanskrit works, including Patanjali's writings and the Manusmriti. He also cited the Vedas and Puranas and worked closely with Brahmana scholars. Hence, Option B is incorrect because it contradicts the documented sources he used.

Despite its length, Kitab-ul-Hind remained accessible because Al-Biruni organized it into eighty chapters following a clear and predictable structure. Scholars describe this arrangement as almost geometric in precision. Therefore, Option C correctly explains its simplicity and lucidity.

Kitab-ul-Hind explored numerous fields, including religion, philosophy, astronomy, alchemy, law, and metrology. Metrology specifically refers to the science of measurement. Therefore, Option D correctly identifies the term used in the text.

Al-Biruni generally began each chapter by posing a question, then presented a description grounded in Sanskritic traditions, and finally compared the subject with practices in other cultures. This consistent structure gave the text clarity and precision. Thus, Option A is correct.

Al-Biruni attempted to understand Indian society comparatively. To explain the caste system, he looked for similarities in ancient Persian society and other civilizations. This method helped him interpret unfamiliar institutions. Therefore, Option B correctly reflects his analytical approach.

Al-Biruni translated important Sanskrit works to facilitate the exchange of knowledge between different civilizations. His translation of Patanjali's work reflected his interest in comparative linguistics and cross-cultural understanding. It was not intended to teach Arabic grammar, introduce Greek philosophy, or criticize Indian texts. Therefore, Option C is correct.

Al-Biruni translated Euclid into Sanskrit to share scientific and mathematical ideas with Indian scholars. This reflects his openness toward intellectual exchange and comparative scholarship. He neither rejected Arabic mathematics nor hid knowledge. Therefore, Option D correctly captures the purpose of this translation.

Al-Biruni regarded language as a major barrier because Sanskrit differed significantly from Arabic and Persian in vocabulary, structure, and concepts. These differences complicated translation and cultural understanding. Therefore, Option D correctly explains why language remained an obstacle despite his linguistic abilities.

According to Al-Biruni, language differences, religious differences, and the self-absorption of local communities created barriers to understanding. This self-absorption produced insularity, limiting interaction with outsiders. Therefore, Option A correctly completes the statement.

Al-Biruni argued that social divisions existed in many societies and were not unique to India. He also observed that Islam emphasized equality among believers except in piety. However, this Islamic principle does not explain his conclusion about social divisions in other societies. Hence, both statements are true, but the Reason is not the correct explanation.

Al-Biruni observed that Vaishyas and Shudras often lived together in the same towns and villages and were mixed within households. This observation suggests that social realities were more flexible than rigid textual descriptions sometimes implied. Therefore, Option C is correct.

Al-Biruni criticized the idea of social pollution by arguing that nature continuously restores purity. He cited examples such as the sun purifying the air and salt cleansing the sea. These observations led him to reject notions of permanent impurity. Therefore, Option D is correct.

Al-Biruni's interpretation of the caste system was strongly influenced by normative Sanskrit texts authored and preserved by Brahmanas. Since he depended largely on Brahmanical sources, his description reflected their perspective. Therefore, both the Assertion and Reason are true, and the Reason correctly explains the Assertion.

The passage highlights that Al-Biruni's dependence on Brahmanical texts produced a rigid picture of caste. Modern historians note that actual social life was more complex because groups such as the antyaja participated in economic networks despite social discrimination. Therefore, Option B accurately reflects this disparity.

The passage states that antyaja groups provided inexpensive labour to peasants and zamindars. Although they experienced social oppression, they remained connected to economic life and production networks. Therefore, Option C correctly captures their practical role within society.