Final answer:
The expression that determines whether x is less than or equal to y is 'x <= y'.
Step-by-step explanation:
The expression that will determine whether x is less than or equal to y is x <= y. This expression represents 'x is less than or equal to y'. In this case, the '<=' symbol is used to indicate less than or equal to.
For example, if x = 3 and y = 5, the expression x <= y would be true because 3 is indeed less than or equal to 5.
On the other hand, options a, b, c, and e do not accurately represent the condition of 'x being less than or equal to y'.