The answer is anagen. Anagen is the active growth phase, when the follicle is actually producing new hair.
Catagen and telogen are the other two phases in the cycle — catagen is a short transition stage, telogen is the resting stage before the strand sheds. Androgen isn't a growth phase at all, it's a hormone category, thrown in as a distractor to catch anyone who mixes up hormone terms with cycle terms.
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