The numbers 1, 5, 8, 9, 10, 12 and 15 are distributed into groups with one or more numbers. The sum of the numbers in each group is the same. What is the largest number of groups? 
选项为:A:$$2$$  B:$$3$$  C:$$4$$  D:$$5$$  E:$$6$$  请回答其中一个选项.