Answer :

To determine which of the given options is not an arithmetic operator, let's review the function of each symbol:

- Option A: A
- Option B: +
- Option C: %
- Option D: >=

1. Option B: + - This is an arithmetic operator used for addition.
2. Option C: % - This is an arithmetic operator known as the modulus operator, which gives the remainder of a division.
3. Option D: >= - This is a comparison operator, not an arithmetic operator. It is used to compare two values to determine if the first is greater than or equal to the second.
4. Option A: A - This is simply a letter and does not function as an operator in arithmetic operations.

Based on the review, the letter "A" is not an arithmetic operator. Therefore, the correct answer is:

Option A: A