In which scenario is recursion likely to be less efficient than iteration?

Recursion is likely to be less efficient than iteration in scenarios where stack memory is limited. This is because each recursive function call adds a new layer to the call stack, consuming additional memory with each call. If there are many nested calls or if the recursion goes too deep, it can lead to stack overflow errors or excessive memory consumption, especially when compared to iteration, which typically uses a fixed amount of memory regardless of the number of iterations.

In contrast, if an algorithm is inherently recursive, using recursion may actually align well with its natural structure, making it more readable and easier to implement. Detailed tracing is often more manageable with recursion since the state can be tracked at each level of the call stack, and functions returning results quickly might not pose issues for either recursion or iteration concerning efficiency.

Thus, when stack memory is limited, recursion poses significant challenges that can impact its efficiency compared to iteration.