Answer:
B. a center of operations
Step-by-step explanation:
According to the text above, a harbor was described by the narrator which was well protected from the sea although the sea was easily reachable through navigable waters.
In the second sentence, it was mentioned that the vessel sailed for the Dutch West India Company with the mission to purchase from the natives a base from which to conduct business trade.
The word base as used here means a center of operations