Look at this series: 4, 7, 25, 10, __, 20, 16, 19, ... What number should fill the blank?  Choose the correct option:
A) 15	B) 13	C) 17	D) 19	E) 11
B   13   Two series alternate here, with every third number following a different pattern. In the main series, 3 is added to each number to arrive at the next. In the alternating series, 5 is subtracted from each number to arrive at the next.
<result>B</result>
Look at this series: 4, 7, 25, 10, __, 20, 16, 19, ... What number should fill the blank?