Find the domain and range of the relation and determine whether it is a function.

A. domain: positive integers; range: positive integers; No, it is not a function.
B. domain: x>-0; range: y>-2; No, it is not a function.
C. domain: all real numbers; range: all real numbers; Yes, it is a function
D. domain; x>-2; range: y>0; Yes, it is a function