Answer: C
Step-by-step explanation:
If (X + 8) is a factor of f(x), then to find the root, equate the factor to zero. That is,
X + 8 = 0
X = 0 - 8
X = -8
If -8 is substituted into f(x), the equation will tend to zero. That is,
F( -8 ) = 0
C is therefore the correct answer.