An Example of Communal Sharing Is

An example of communal sharing is

A) people exchanging Christmas gifts with each other.
B) buying something from eBay,where the seller's relationship with the buyer is independent of price.
C) a family in which each person takes turns taking out the garbage.
D) an office with a jar of coins,where workers can take or put in as many coins as they like.
E) the elder of a community giving away his wealth.