Which is correct?
d. he or she (alternatively, she or he)
Answer: a. — if you follow AP or Chicago style. If you aren’t constrained by a particular style, e. (they) is the best option.
It’s called the generic he, used to represent a single person whose gender is not specified. But of course, he is not generic — it refers to a single male person. Both the AP Stylebook and the Chicago Manual of Style say you should use he if you get yourself into a situation where you need a generic pronoun. They both also recommend that you try to avoid that situation or rewrite your sentence to get out of it.
Which seems a little cowardly to me — really, if they recommend he as the appropriate generic pronoun, they should at least stand by their choice and recommend that you use it freely as required by your sentence.
Singular they is nothing new. Here’s what Paul Brians has to say about it: Using the plural pronoun to refer to a single person of unspecified gender is an old and honorable pattern in English, not a newfangled bit of degeneracy or a politically correct plot to avoid sexism (though it often serves the latter purpose).
Motivated Grammar also has a nice post on singular they and its use by well-respected writers for hundreds of years.
I expect that singular they will become acceptable, especially considering that rules tend to follow use and use online overwhelmingly favors it. In the meantime, however, you have options: You can take the coward’s way out and rewrite your sentence or boldly buck the rules and use it anyway. I like the second alternative — if enough of us take it and we stand our ground, style guides will have to bow to the inevitability of singular they.
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