Starting their foothold on coastal locations, they first developed some trading ports such as Surat, Daman, Goa, Pondicherry, etc. The British later consolidated their hold around three principal nodes – Mumbai (Bombay), Chennai (Madras), and Kolkata (Calcutta) – and built them in the British style.

Mumbai (formerly known as Bombay): Mumbai was a vital port city and a key economic center. The British East India Company initially established its presence in India here. Mumbai served as a major hub for trade, both within India and with the British Empire, due to its strategic location on the western coast. 

Kolkata (formerly known as Calcutta): Kolkata was another important city for the British. It became the capital of British India in 1772 and remained so until 1911. The British East India Company set up its headquarters in Kolkata, making it a significant administrative and commercial center for the company. 

Chennai (formerly known as Madras): is a coastal city on the Bay of Bengal, making it a prominent port for trade during the colonial period. The city served as a vital link in the trade routes connecting India with the British Empire and other parts of the world. The British established a significant presence in Chennai to oversee maritime trade and to facilitate the export and import of goods.

So, option 3 is correct.