C
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When hard disk drives became standard in most PCs in the later 1980s, since the first two letters were already commonly used for these floppy drives, they logically labeled the third storage device “C”, even though it now tended to be the main storage medium for the computer, including usually containing the operating system.
Answer:
a simple IF statement using Regex
Explanation:
In any coding language, a good control procedure for this would be a simple IF statement using Regex. In the IF statement you can grab the account code and compare it to a regular expression that represents the correct format. IF the account code is in the correct format (matches the regular expression), then you go ahead and save the account code for use. Otherwise, you would output an error and ask for another account code. This will prevent the program from trying to use an account code that is not valid.