The answer to the question "Hughly was used as a base for piracy in the Bay of Bengal by which country: the Portuguese, the French, the Danish, or the British?" is Option 1: the Portuguese.

Historically, the city of Hughly, also known as Hugli or Hooghly, was a significant trading port located on the Hugli River in the Bengal region of India. During the colonial era, various European powers sought control over this strategic port to establish their dominance in trade and commerce.

The Portuguese were one of the earliest European powers to arrive in the Indian subcontinent in the 16th century. They established several trading posts and forts along the Indian coast, including in Hughly. Initially, the Portuguese focused on trade, but over time, they resorted to piracy to maintain their dominance and control over the Bay of Bengal.

One prominent figure associated with Portuguese piracy in the Bay of Bengal was the pirate and privateer, Pedro Lopes de Sousa. He operated from the Portuguese base in Hughly and conducted pirate raids on merchant ships belonging to rival European powers, as well as local Indian traders.

The Portuguese engaged in piracy as a means to disrupt the trade of their competitors, particularly the Mughals and the British, who were challenging Portuguese dominance in the region. Their activities were driven by a desire to protect their own economic interests and maintain their control over key trading routes.

It`s worth noting that other European powers, such as the French, Danish, and British, also had a presence in the region during this time. However, the Portuguese were known for their piracy activities in Hughly and the Bay of Bengal.

Overall, the historical records and accounts of piracy in the Bay of Bengal during the colonial era predominantly attribute this activity to the Portuguese presence in Hughly.