Study the following series.
M E F 8 $ 6 3 D 9 X H N S K 7 T U G 1 V
Find what should come in place of the question mark(?)
$3, 9H, S7, ?
There is a gap of 3 between the first characters of each of the given pair. The second character of each pair is two positions to to the right of the first character.