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