With reference to Indian history, consider the following statements:

1. The first Mongol invasion of India happened during the reign of Jalal-ud-din Khalji.
2. During the reign of Ala-ud-din Khalji, one Mongol assault marched up to Delhi and besieged the city.
3. Muhammad-bin-Tughlaq temporarily lost portions of north-west of his kingdom to Mongols.

Which of the statements given above is/are correct?

The correct option is 2 only.

Let us analyze each statement step-by-step to understand why only the second statement is correct:

Statement 1 is incorrect:
The first Mongol invasion of India occurred much earlier, during the reign of Shams-ud-din Iltutmish (r. 1211–1236) of the Slave Dynasty. In 1221, Genghis Khan, the leader of the Mongols, reached the banks of the Indus River in pursuit of Jalal-ud-din Mingburnu, the ruler of Khwarazm. Iltutmish wisely refused to give asylum to Mingburnu, thereby saving the Delhi Sultanate from a devastating Mongol assault at that time. Jalal-ud-din Khalji ruled much later, from 1290 to 1296.

Statement 2 is correct:
During the reign of Ala-ud-din Khalji, the Mongols invaded India multiple times. In 1303, a massive Mongol army led by Targhi marched directly to Delhi, bypassing other garrisons. Ala-ud-din Khalji was forced to retreat into the Siri Fort, and the Mongols besieged the city of Delhi. The siege lasted for about two months before the Mongols abruptly withdrew, unable to breach the fortifications and supply lines.

Statement 3 is incorrect:
During the reign of Muhammad-bin-Tughlaq, the Mongols did invade under the leadership of Tarmashirin (around 1327). However, Tughlaq did not lose any portions of the north-west of his kingdom to them. Instead, Tughlaq defeated or paid off the invaders, and he later planned a counter-offensive to secure the frontier regions, consolidating his control rather than losing territories permanently or temporarily to Mongol rule.

Therefore, only Statement 2 is correct.