Known as admiral of the indian ocean

The answer is Vasco Da Gama.

Explanation:

He was a famous portuguese explorer that became the first european to reach india by sea. This voyage was also the first link between Europe and the Asian continent done by an ocean route.

The discovery of the sea route to India was of huge importance in the portuguese's global imperialism that established a variaty of colonies in Asia that later became an entire empire for the portugueses.

Regarding all of his merits, on the 30th of January of 1502, Da Gama was awarded with the title of "Admiral of the Seas of Arabia, Persia, India and all the Orient".

a is correct

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