What is the meaning of this aphorism from Paine's The American Crisis?

What we obtain too cheap, we esteem too lightly.

A. If we want to win a war, we have to sacrifice all that we consider
inexpensive.

B. When people win a victory easily, they do not appreciate the
results.

C. When people sacrifice too much for a victory, they do not
appreciate the results.

D. If we are not determined enough, our enemies will not respect us.