An ice cream stand was selling ice cream in five different flavors. A group of children came to the stand and each child bought two scoops of ice cream with two different flavors. If none of the children chose the same combination of flavors and every such combination of favors was chosen, how many children were there? 
选项为:A:$$5$$  B:$$10$$  C:$$20$$  D:$$25$$  E:$$30$$  请回答其中一个选项.