Can yall help me out

Devon wanted to know if x−3 is a factor of f(x)=x^3+x^2−10x+8. She applied the Factor Theorem and concluded that x−3 is not a factor of f(x), as shown in the following work.

f(−3)=(−3)^3+(−3)^2−10(−3)+8=20
f(−3)=20, so the remainder is 20.
The remainder is 20, so x−3 is not a factor of f(x).

Did Devon make a mistake? If so, what was her mistake?

A. Yes, x−3 is a factor of f(x).
B. Yes, Devon evaluated f(−3) incorrectly.
C. No, Devon did not may any mistakes.
D. Yes, Devon should have evaluated f(3).
E, Yes, f(−3)=20 does not mean the remainder is 20.