Question
Find Missing Number?

A. 2
B. 1
C. 21
D. 20
Answer: A
Solution:
Now we have a pattern of prime numbers because 2 is the 1st prime number and all other numbers are prime numbers.
Therefore
2, 3, 5 , 7 , 11 , 13 , 17, 19 . are in prime number series pattern.