Refer to the following series and answer the question (all numbers are single digit numbers only).
(Left) 1 5 7 9 5 8 5 7 6 2 1 3 7 4 2 1 5 6 9 7 4 3 5 2 3 4 3 (Right)
How many such even digits are there each of which is immediately preceded by an odd digit and also immediately followed by an odd digit? ​​

Given: (Left) 1 5 7 9 5 8 5 7 6 2 1 3 7 4 2 1 5 6 9 7 4 3 5 2 3 4 3 (Right)

Logic: Odd Digit | Even Digit | Odd Digit

5 even digits are there each of which is immediately preceded by an odd digit and also immediately followed by an odd digit.

Thus, correct option is (a).