Answer:
A. f(2k)=0
Explanation:
The factor theorem states that a polynomial f(x) has a factor (x−k) if and only if f(k)=0 (i.e. k is a root).
If (x – 2k) is a factor of f(x), then by the factor theorem f(2k)=0 (i.e. 2k is a root).
Option A is true, f(2k)=0
Option B is false, it should be like in option A, f(2k)=0
Option C is false, because x=2k is a root, not x=-2k
Option D is false, because x-intercept of f(x) is x=2k, not y-intercept.