State whether each of the following is true or false. If false, explain why.

a) A method that calls itself indirectly is not an example of recursion.

b) Recursion can be efficient in computation because of reduced memory-space usage.

c) When a recursive method is called to solve a problem, it actually is capable of solving only the simplest case(s), or base case(s).

d) To make recursion feasible, the recursion step in a recursive solution must resemble the original problem, but be a slightly larger version of it.