What causes 'big' quads on women?

I hope y'all know what quads are lol

but quads like these:

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^I have legs like her, which I personally don't like

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but I those big quads, imo. what causes those?

I would post pics...but I know it's not allowed and I won't unprivate my profile for people to see
What causes 'big' quads on women?
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