Clarke’s Coffee

From Twitter
Jo: How __ that girl eat out so often? She works at Clarke’s Coffee.
Bo: Is that the place that has 2001 flavors?
Jo: Yeah!
Bo: They don’t make any money at Clarke’s. And She wears fancy clothes too. She posts on Instagram.

Answer And Explanation:
The answer is ‘can,’ because ‘could’ suggests unreality and/or the future, but this conversation refers entirely to the present about present tense events.