What country's capital sinks every year

Mexico

Explanation:

The country's capital that sinks every year is Mexico. The capital  Mexico city  is built on a lake in the southern part of Meseta and it sinks every year by half a foot. Mexico city is the largest and the most populous city in Mexico and the whole of North America. it is very reach in cultural displays and traditions it is the country's most important economic, political, and cultural center. and also one of the important economic hubs/center in the whole of Latin America. it's name was official change to mexico city by president  Enrique Pena Nieto.

the first part is ocean

explanation:

c. reserves power to the states and people