Correct option is A
Given:

Logic: Sum of square box Numbers = Sum of the square of the star Numbers
In Figure 1:
12 + 8 = (2)2+ (4)2
20 = 4 + 16
20 = 20
In figure 2:
6 + 4 = (3)2+ (1)2
10 = 9 + 1
10 = 10
Similarly, In Figure 3:
? + 19 = (5)2+ (2)2
? + 19 = 25 + 4
? = 29 -19
? = 10
So, the missing number is 10.
Thus, the correct option is (a)






