One can expect a recurive algorithm is more efficient than its iterative counterpart if

a$.$

The recursive algorithm multiplies the input by a constant number at each call of the recursive function.

b$.$

The recursive algorithm divides the input by a constant number at each call of the recursive function.

c$.$

The recursive algorithm adds the input by a constant number at each call of the recursive function.

d$.$

The recursive algorithm subtracts the input by a constant number at each call of the recursive function.