Question

The main cause of Blackhole incident was that______.
A. British company supported Shaukat Jang, the rival of Siraj ud Daulah.
B. The British Company started making forts in Bengal without the permission of Siraj ud Daulah
C. The British people gave shelter to a rich businessman who was demanded by Siraj ud Daulah
D. British Company was not ready to recognise Siraj ud Daulah as a Nawab.

Answer 1

Hint: The black hole incident of Calcutta dated back to the night of 20 June 1756. The troops of European army were captured and locked in the black room for three days by the Nawab of Bengal resulting in the death of many by suffocation; this whole incident is known as the black hole.

Complete answer: Nawab Sirajuddaula challenged the British activities and stopped paying the customs duties in Bengal and the flow of revenue to the company officials as he was very suspicious of English activities.
During 1756, when the army of East India company started military preparedness at Fort William in Calcutta, Nawab Siraj ud-daulah asked them to stop and move back. However, when the British didn't hold back, his army held the British as prisoners in the black rooms of fort William which were 22 feet long and 14 feet wide. Out of 146 British officers, 123 died of suffocation and very few survived.
-After the incident of Blackhole the East India Company decided to attack Siraj-ud-daulah and throw him out. The company offered Mir Jafar the throne of Bengal who was the commander in chief of the nawab army. Mir Jafar sent the letter to Shaukat Jang and urged him to invade Bengal and assured him of his support as well as the army and the court of Murshidabad however Siraj ud daulah came to know about the conspiracy and he prevented it in time.
-It was during the Battle of Plassey in 1757 that British forces successfully overthrew Sirajuddaula from the throne and ascended Mir Jafar to the throne. However, after the war, it became the main source of British rule in India.
There is no mention of Britishers giving shelter to rich businessmen during the Blackhole incident and its aftermath.
Therefore the correct answer is option-B.

Note: It is also important to note that during that time Britishers had only direct control over a small number of areas and were highly dependent on the nawabs of princely states for revenues, therefore, John Holwell was a governor of that area and had only limited military experience and was forced to surrender to the nawab on the afternoon of 20th June.