Can you find the missing number in the sequence given below?
10 15 20 11 16 ? 12 17 22 13 18 23
Choose one:  A) 25  B) 23  C) 21  D) 18  E) 19
Let's break the given series as below:   10 15 20   11 16 ?   12 17 22   13 18 23   Now read the number from left hand side from top to bottom as :   So the number that will replace '?' is 21   Answer : 21
<result>C</result>
Can you find the missing number in the sequence given below?
10 15 20 11 16 ? 12 17 22 13 18 23