The single Russian port that's not frozen over for part of the year is located on the

AMediterranean Sea.
BPacific Ocean.
CBlack Sea.
DBaltic Sea.

Verified Answer :

The Russian port that is not frozen over for part of the year is located on the Mediterranean Sea.

There is only two ports that are not frozen.
-Vladivostok, Pacific Ocean
-Murmansk, Arctic Ocean

Answer:
B. Pacific Ocean