How do I figure out if my crush is single or not?

There's this cute girl in my class and I want to ask her out, but I don't know if she's single... and I don't want to make it uncomfortable for either of us. I provided options below that I consider doing
Just ask her out. No risk no fun
Text her on social media first
Ask other class mates if they know
Other (comment below)
Select gender and age to cast your vote:
How do I figure out if my crush is single or not?
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