What was the main reason for the defeat of Sirajuddaulah at the Battle of Plassey?

Forces led by commander Mir Jafar never fought the battle.

The correct answer is Option 2- Forces led by commander Mir Jafar never fought the battle.

The main reason for the defeat of Sirajuddaulah at the Battle of Plassey in 1757 was betrayal within his own ranks. Mir Jafar, the commander of Sirajuddaulah's army, conspired with the British East India Company led by Robert Clive. Mir Jafar secretly agreed to defect to the British side during the battle, which significantly weakened Sirajuddaulah's forces. This betrayal, along with other factors such as the superior military tactics of the British and their alliances with local Indian rulers, contributed to Sirajuddaulah's defeat at Plassey.