The shoes fitted her______ . It was a pity that she didn't buy them then.

A．picked out four people to conduct a public-goods game
B．sold each player many tokens at a very high price
C．asked the players to make all of their values increase
D．believed the behavior of those persons to be quite honest

A．the subjects have very little influence to others
B．all the participants belong to three categories
C．people may change their strategies whenever necessary
D．the strategies of the games are actually dependable