问题如下：
For a swap in which a series of fixed payments is exchanged for a series of floating payments, the parties to the transaction:
选项：
A. designate the value of the underlying at contract initiation.
B. value the underlying solely on the basis of its market value at the end of the swap.
C. value the underlying sequentially at the time of each payment to determine the floating payment.
解释：
C is correct. On each payment date, the swap owner receives a payment based on the value of the underlying at the time of each respective payment.
A is incorrect because in a swap involving a series of fixed payments exchanged for a series of floating payments, each floating payment reflects the value of the underlying at the time of payment, not a designated value at contract initiation.
B is incorrect because in a swap involving a series of fixed payments exchanged for a series of floating payments, each floating payment is based on the value of the underlying at the time of each respective payment, not on the market value at the end of the swap.
a选项，解答说问题在designate，不是指定的日期，而是跟swap利率交换日期一直。可是利率交换日期也是发行时候就确定好的，不是吗？如果这样也就是指定的意思=designate
