how much or how often or how larg

[Huda2]

hello,
which one is correct?
"How _____ a crowd had gathered at the scene of the accident?"
"I don't know exactly, but there were a lot of shocked onlookers."
large
often
many
much

thanks in advance

[Kitosdad]

Large seems to be the likely answer, but it a badly couched reply.
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