If you receive a gift whose market price is $20, but you consider it to be worth only $10, then

A) there is a $10, or 50 percent, value gain.
B) there may or may not be a value loss.
C) there is a $10, or 50 percent, value loss.
D) you can be relatively certain the giver was a sibling or other close relative.

A high inflation rate in a country will make its currency gain value against others.