The correct answer is C) to capture bases and forts in order to exert increasing influence over the region.
The main goal of Portugal, in terms of increasing trade within the Indian Ocean basin, was to capture bases and forts in order to exert increasing influence over the region.
It was Portuguese navigator Vasco de Gama established a safe route to the Indian Ocean. That is when they started to trade in the zone, and displaced Asian nations as the prominent kingdom that traded in the region. Let's remember that the Portuguese were great explorers and navigators. Indeed, Prince Henry of Portugal called the Navigator, opened a school of navigation to support maritime discoveries.
