Why does ECC provide more protection with a smaller key when compared to other asymmetric algorithms?

A.
It is based on discrete logarithms instead of factoring

B.
There is no known sub-exponential algorithm for it

C.
It requires a smaller amount of processing resources

D.
It works within a finite field

Explanation:
There is no known sub-exponential algorithm for computing discrete
logarithms of points of elliptic curves, like there is for finite fields.