Answer : 1. "33"
Explanation :

Answer: A) 33 Explanation: The given series follows a pattern that, +4, +6, +8, +10, +12... 5 5 + 4 = 9 9 + 6 = 15 15 + 8 = 23 23 + 10 = 33 33 + 12 = 45   Hence, the missing number in the series is 33.