why is לוקח wrong? should be right too!
Only because it is a girl speaking so she would say אני לוקחת
I have a drop-down menu exercise, there is no voice, hence there is no way to know.
There's voice now
There is no indicator that it is a girl.
She's speaking, but even if she wasn't you know because of the tense..
There's audio I think maybe the question has changed since you asked. I can't tell because I'm in the app. It's 7 May 2018, and there's Hebrew & audio to translate into English.
Ahh! Peach thieves!
לוקח is correct
Ani lokachet afarsek
I don't know why it's in the infinite tense. How do we know when to use this?
It's not infinitive: that's lakakhat. The vav indicates that this is lokakhat, i.e. first person sing. fem. See https://www.pealim.com/dict/2427-lakachat/