Answer:
Option C.
Explanation:
We need to translate each phrase and find the different expression. 
"+" sign is used for sum, more and total. 
Twice means two times of a number. 
Let n be the unknown number. 
Two more than a number = n+2 
The total of n and 2 = n+2 
Twice the number n = 2n 
Sum of n and 2 = n+2 
From the above expressions it is clear that only 2n is different from other. 
Therefore, the correct option is C.