单选题The symbol ☆ represents one of the fundamental arithmetic operators：+, -, ×, or ÷. If (x☆y)÷(y☆x)=1 for all positive values of x and y, then ☆ can represent ______.A + onlyB ÷onlyC + or × onlyD - or × onlyE +, -, ×, ÷
题目
单选题
The symbol ☆ represents one of the fundamental arithmetic operators：+, -, ×, or ÷. If (x☆y)÷(y☆x)=1 for all positive values of x and y, then ☆ can represent ______.
A
+ only
B
÷only
C
+ or × only
D
- or × only
E
+, -, ×, ÷