Answer: A symmetric payoff profile.

A standard interest rate swap is characterized by a **symmetric payoff profile**, meaning the swap has zero value to both parties at contract inception. This aligns with the nature of interest rate forwards and swaps, where no cash flow is exchanged upfront. Option B is incorrect because no principal cash flow is exchanged upfront in a standard swap. Option C is incorrect because periodic settlements in a standard swap occur at the **end** of each period, not the beginning, distinguishing it from a forward rate agreement (FRA), which settles at the beginning of the interest period.

Author: LeetQuiz Editorial Team