The fourth line of the main heading of a memo is the line. A. Date B. Subject C. From D. To

B. Subject

Explanation:

It's subject. There are four steps to a memo, the first step is the person it's going to, the second is from the person that sent it, the third step is the date it was sent, and finally the last step is what the memo is about, which is the subject.

Note:

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