There are many idioms in this exercise! From c), “throw in the towel” means to give up or quit. It implies defeat, like you lost a fight. From e), “lay your cards on the table” means to show what you have, literally what playing cards you held in your hand in a game of poker. “Clear the air” means to have a conversation to clarify or address a misunderstanding or conflict. It implies there are unspoken things that are making a situation difficult or tense because they aren’t being acknowledged.

Interesting question! Personally I can’t see that any of them are really “collaborating” because that means working together to achieve something. So this is tricky because there are fine differences between a lot of these. I tried to work it so there are two of each where they seem the best answers. A 1 B 5 C 4 D 3 E 2 F 2 G 5 H 3 I 4 J 1

not sure but here's my version a 1 b 5 c 3 d 5 e 4 f 2 g 4 h 2 i 3 j 1