Option a is the correct answer. The Red Fort of Delhi was built by Akbar's grandson Shah Jahan, who shifted the capital from Agra to Delhi in 1638. The Red Fort is a massive fortification that served as the main residence of the Mughal emperors for nearly 200 years. It is also a UNESCO World Heritage Site and a symbol of India's heritage. Important Tips The Agra Fort was the first fort that Akbar built in 1565, and it was the seat of power for the Mughal empire for about 150 years. It is also a UNESCO World Heritage Site and one of the most impressive monuments in Agra. The Allahabad Fort was built by Akbar in 1583 at the confluence of the Ganges and Yamuna rivers. It was a strategic and religious site, and it also housed a famous Akshayavata tree, where people would commit suicide to achieve salvation. The Lahore Fort was built by Akbar in 1566, and it was the largest fort built by him. It was also the residence of his son Jahangir and his wife Nur Jahan, who were influential rulers of the Mughal empire