Correct answer: A. On grand buildings beauty and the peak of marble style
Explanation: The direct answer is option A: the idea of a golden age of architecture in Shah Jahan’s reign is based on grand buildings, refined beauty and the high development of Mughal marble architecture. Shah Jahan’s period is associated with impressive monuments such as the Taj Mahal, the Red Fort and the Jama Masjid. These buildings show careful planning, large scale, balanced design, decorative work, arches, domes, gardens and extensive use of marble and inlay. Therefore historians connect his reign with the peak of Mughal architectural achievement, although “golden age” is a descriptive phrase and does not mean every part of society was equally prosperous. Option A is correct because it gives the architectural basis. Option B is wrong because the Chola navy belongs to a different southern dynasty and period. Option C is wrong because Gupta education is unrelated to Shah Jahan’s buildings. Option D is wrong because Sultanate coinage concerns money and an earlier political context, not the architectural achievements of the Mughal emperor. Memory cue: “Shah Jahan = Taj Mahal, marble, symmetry and Mughal grandeur.”