Option c is the correct answer. Qutab-ud-din Aibak, the first Muslim ruler of Delhi, commenced the construction of the Qutab Minar in 1200 AD, but could only finish the basement. His successor, Iltutmush, added three more storeys, and in 1368, Firoz Shah Tughlak constructed the fifth and the last storey. The first three storeys are made of red sandstone; the fourth and fifth storeys are of marble and sandstone. At the foot of the tower is the Quwwat-ul-Islam Mosque, the first mosque to be built in India. It is a UNESCO World Heritage Site in the Mehrauli area of South Delhi, India.