Given a text T, and several options, according to the question posed in the text T to choose the most appropriate option from the options as the answer, please directly output the most appropriate option, do not need to output the explanation.

With respect to a forward contract, as market conditions change:
Option A:only the price fluctuates.
Option B:only the value fluctuates.
Option C:both the price and the value fluctuate.

Answer: B