Question

the red star is marking the body of water known as the
a baltic sea.
b north sea.
c bosporus strait.
d english channel.

Explanation:

The red - star is located in the northeastern part of Europe, which is the location of the Baltic Sea. The North Sea is to the west of the British Isles, the Bosporus Strait is in Turkey connecting the Black Sea and the Sea of Marmara, and the English Channel is between England and France.

Answer:

A. Baltic Sea