Fact 1: Aship is used for moving people across bodies of water. Fact 2: Abundant waters call for stories of travel and trade, and protecting ships from dangers. Given the two facts above, what are used for travel and trade?

Select from:
a). pigeons
b). squids
c). rivers
d). ships
e). oceans
f). horses
g). commissions
h). bikes
The answer is:
d).