If (4x-7) < (2x+13), then which of the following must be true?

A x>9

B x< 13

C x<7

D None of these

Correct Answer: Option C

(4x-7) < (2x+13)

4x - 2x < 13+7

2x < 20

x < 10

Now,

x>9 would allow x to be 11 or higher, which it cannot be.

x<13 would also allow x to be 11 or higher, which it cannot be.

but x<7 has no values of x in it, which cannot be expressed in the original expression "x<10"