Answer:
12 x ≤ 48
Explanation:
This inequality must have two sides, one that shows the expenditure Mary will do in function on the number of shirts (x) and other that shows the maximum money she can spend (48).
Her expenditure will depend on the shirts purchased (x) and as each shirt costs $12 the expenditure will be 12x. So, this expenditure MUST be equal or less to the maximum she can pay: $48.
The inequality will be:
12 x ≤ 48
This is the first of the options posted. From the others, none of them work.