Which of the following was the capital of Qutb-ud-din Aibak, the founder of Slave Dynasty?

The correct answer is: B. Delhi

Qutb-ud-din Aibak was the founder of the Slave dynasty, which ruled over the Delhi Sultanate from 1206 to 1290. He was a slave of Muhammad Ghori, the ruler of the Ghurid dynasty, who conquered Delhi in 1192. After Ghori’s death in 1206, Aibak became the sultan of Delhi. He made Delhi his capital and built many important buildings there, including the Qutb Minar, a minaret that is one of the tallest brick towers in the world.

Lahore was the capital of the Ghaznavid dynasty, which ruled over the Punjab region from the 10th to the 12th centuries. Agra was the capital of the Mughal Empire from the 16th to the 18th centuries. Lucknow was the capital of the Nawabs of Awadh from the 18th to the 19th centuries.