Refer to the following letter and number series and answer the question.
(Left) G C T 7 D 4 6 K 2 R Y 3 5 E S A 4 T Y 7 8 G T (Right)
How many such letters are there in the series which are immediately preceded by a letter and also immediately followed by a number ?
1
Two
2
Three
3
Four
4
None