1- The correct answer is C. The Portuguese establishment of trading posts throughout the Indian Ocean had a great impact on Europe, as it encouraged other European nations to explore and establish colonies, in order to obtain the same benefits as Portuguese obtained by establishing such colonies (cheaper prices, lower costs to move goods, trading exclusivity).
2- The correct answer is C. The Portuguese used both diplomacy (Macau and Mumbai, for example) and force (the case of Goa, among others). In this way, they took possession of numerous ports and coastal cities, extremely important for the control of trade in the area.
3- The statement that is true is A. The Portuguese were the first to connect with Asia through the Indian Ocean, since previously the contact was made through the Middle East. Upon finding this new route, they obtained great benefits because they no longer had to pay taxes to move their products overseas.
4- The answer is D. The possibility of accesing the internal rivers was the greatest interest that Portuguese had when establishing their colonies, since in this way they could control not only the coast but also the commerce with inland towns.