Which party observed the “Black Day” on July 3, 1947 against Partition of India?
[A] Indian National Congress
[B] Forward Bloc
[C] Hindu Mahasabha
[D] Communist Party of India

Hindu Mahasabha
. 3 June Plan or Mountbatten Plan was the partition of British India on the basis of religious demographics. This led to the creation of the sovereign states of the Dominion of Pakistan.