Study the following alphanumeric symbol series carefully and answer the questions given below:
F 4 A % T 9 µ Z M 3 N # L & E 2 X C 7 G D * O 5 R ∞ H 1 J $ @ K 8 B

How many letters are there which are immediately preceded by a symbol and immediately followed by a digit?

To solve this question, we need to find all the letters in the given alphanumeric symbol series that satisfy the following condition:
1. Immediately preceded by a symbol (i.e., a symbol is directly before the letter).
2. Immediately followed by a digit (i.e., a digit/number is directly after the letter).

Therefore, we are looking for the following pattern sequence:
[Symbol] [Letter] [Digit]

Let us analyze the given alphanumeric series step-by-step to identify all occurrences of this pattern:
Series: F 4 A % T 9 µ Z M 3 N # L & E 2 X C 7 G D * O 5 R ∞ H 1 J $ @ K 8 B

Let us inspect the combinations:
1. % T 9: Here, the letter T is immediately preceded by the symbol % and immediately followed by the digit 9. (Match 1)
2. & E 2: Here, the letter E is immediately preceded by the symbol & and immediately followed by the digit 2. (Match 2)
3. * O 5: Here, the letter O is immediately preceded by the symbol * and immediately followed by the digit 5. (Match 3)
4. ∞ H 1: Here, the letter H is immediately preceded by the symbol ∞ and immediately followed by the digit 1. (Match 4)
5. @ K 8: Here, the letter K is immediately preceded by the symbol @ and immediately followed by the digit 8. (Match 5)

There are a total of 5 such letters (T, E, O, H, and K) that satisfy the condition. Since 5 is greater than four, the correct answer is More than four.