Find the missing number?

A. 2

B. 5

C. 9

D. 13

Answer: Option C

Solution(By Examveda Team)

Using the top two grids as a source, numbers in the lower left grid equal the sums of numbers in corresponding positions of the top two grids, subtracting 1 each time, and numbers in the lower right grid equal the differences between numbers in corresponding positions of the top two grids, adding 1 each time.