Correct Option: C

In 1757, Sirajuddaulah attacked British factory at Kasimbazar. Sirajuddaulah asked the Company to stop meddling in the political affairs of his dominion, stop fortification, and pay the revenues. After negotiations failed, the Nawab marched with 30,000 soldiers to the English factory at Kasimbazar, captured the Company officials, locked the warehouse, disarmed all Englishmen, and blockaded English ships. Then he marched to Calcutta to establish control over the Company's fort there.