问题如下：
Which of the following derivatives is a contingent claim?
选项：
A. fixed-for-floating interest rate swap
B. credit spread option
C. bond index futures
解释：
B is correct. Swaps and futures are forward commitments because the parties have obligation to engage in a future transaction. Options are contingent claims because one party has the right but not the obligation to engage in a future transaction.
这道题可以解释下吗？
