East asia’s ocean and inland waters have been an important source of for the region’s people.
food
industrial development
irrigation
hydroelectricity

East Asia's ocean and inland waters have been an important source of irrigation for the region's people.

C

Explanation

Most civilizations of ancient history owe to water bodies.

As people always desire to stay at a place where there would be sources that can fulfill their daily needs.

The most effective places where people could find all the sources combined are lands near the water bodies.

This land has many favorable characters like good fertile soil, irrigation for the cultivation of crops which is the major source of food, manufacture of utensils etc.

Irrigation is widely practiced due to the availability of these water bodies.

the answer is:

c. economic output

the answer would be c. sediment buildup on continental slope

                                                                                -hope this -