Look at this series: V, VIII, XI, XIV, __, XX, ... What number should fill the blank? Choose the correct choice from the following answers
A) IX	B) XXIII	C) XV	D) XVII	E) None
Explanation: This is a simple addition series; each number is 3 more than the previous number.   Answer: Option XVII
<result>D</result>
Look at this series: V, VIII, XI, XIV, __, XX, ... What number should fill the blank?