At an ice cream shop, a sundae is made by selecting two flavors of ice cream and topping them with fudge, whipped cream, nuts, and a cherry. The available flavors of ice cream are chocolate, vanilla, strawberry, rocky road, chocolate chip cookie dough, and mint chip. How many difference sundae combinations are possible? 
选项为:A:$$2$$  B:$$15$$  C:$$24$$  D:$$120$$  E:$$720$$  请回答其中一个选项.