Ascii

Step 1: Understand ASCII.
ASCII (American Standard Code for Information Interchange) assigns numeric values to characters.
Step 2: Recall standard ASCII values.
The uppercase letter `A' starts at ASCII value 65.
Step 3: Compare with other options.
64 is before `A'.
97 is the ASCII value of lowercase `a'.
90 is the ASCII value of `Z'.
Step 4: Conclusion.
Hence, the ASCII value of `A' is 65.