The correct answer is A because the fixed-rate receiver pays the market reference rate (MRR) and receives the fixed swap rate. If the MRR increases, the fixed-rate receiver is obligated to pay more, thereby reducing the contract's value to them.

An alternative interpretation is that the fixed-rate receiver is effectively long a fixed-rate bond (receiving the swap rate) and short a floating-rate note (paying the MRR). A rise in the MRR increases the present value of the floating payments (liability), while the fixed payments (asset) remain unchanged, leading to a decline in the swap's value.