3 holes.
"Bottles/Cans" - This refers to the end form of the objects going in there (glass? plastic? aluminum? tin? unclear).
"Paper" - This is a material. Ideally separated for recycling.
"Trash" - A judgment.
I'm sure I'm overthinking it, but I can think of a million objects that don't neatly fit into any of the wholes on this multiple choice puzzle. Kills me every time. (See also doors that require instructions.)