A data set consists of~~(not distinct) positive integers: 1,7,5,2,5 and x. The average (arithmetic mean) of the~~numbers equals a value in the data set. What is the sum of all positive values of x? 
选项为:A:$$10$$  B:$$26$$  C:$$32$$  D:$$36$$  E:$$40$$  请回答其中一个选项.