Question

What mechanism defines tail recursion?

A. The calculated answer is propagated to each layer of the recursion through the parameters
B. The recursion "coils" itself up like a spring, eventually reaching a base case and allowing waiting calculations to finish
C. A shallow inheritance structure is used and each object stores another object of the same type allowing you to call through the stack of objects as a whole calculation
D. Multiple recursive cases are used creating a "search space" of possible calculated recursive solutions. At a certain point a consideration path can be abandoned for another path.

Answer 1

Tail recursion is a recursion where the function's last operation is a call to itself, with no further operations after that. The correct mechanism is that the calculated answer is passed through the parameters, allowing for tail call optimization which prevents stack overflow.

Step-by-step explanation:

Tail Recursion Explained

Tail recursion is a specific kind of recursion where the last operation of a function is a call to itself and there are no further operations or computations afterwards. Option A describes this mechanism correctly: The calculated answer is propagated to each layer of the recursion through the parameters. Typically, in tail recursion, the function's return value is the same as the return value of the recursive call, which means that there is no need to keep the current frame on the call stack. As a result, a compiler or interpreter that recognizes tail recursion can optimize the recursive calls to avoid consuming additional stack space, effectively turning the recursive process into an iterative one. This optimization is called tail call optimization (TCO), and it prevents stack overflow errors that can occur with deep recursion.