Imma take a guess maybe C
You can turn 5 into 10/2 and add to x/2
then you need to use simple algebra to left the x alone in the equation so you need to multiply both sides by 2 so you get
2y=10+x
then you need to subtract both sides a 10 so
2y-10=x
now change the x to f'(x) and y to x so:
f'(x)=2x-10
Answer:
C) 
Step-by-step explanation:

Therefore, C is correct. Recall that 
4 consecutive integers...
x, x + 1, x + 2, x + 3
x + x + 1 + x + 2 + x + 3 = 106
4x + 6 = 106
4x = 106 - 6
4x = 100
x = 100/4
x = 25
x + 1 = 25 + 1 = 26
x + 2 = 25 + 2 = 27
x + 3 = 25 + 3 = 28
ur 4 integers are : 25,26,27,28
Last one is your answer.
X cannot be repeated, but y can