A cafe has a lunch special with a base price of $5.00.

It is a DS question. You don't have to solve it. All you have to figure out is whether you can solve it to get a unique solution.

Price of base meal = $5
Total collection = $36000

Stmnt 1: Each possible meal combination generated equal revenue during the month of August.
Total revenue = 36000.
No of possible meal combinations = 5*4*4 = 80
How many of these include grilled cheese sandwich? 1*4*4 = 16
Revenue generated by each meal combination = 36000/80 = 450

Now you can find the number of meals for each combination e.g.
Grilled Cheese - Tomato soup - salad = 450/5 = 90
Grilled Cheese - Tomato soup - chips = 450/5 = 90
.
.
Grilled cheese - Clam chowder - salad = 450/6.25 = 72
.
etc

Addition of all these number of meals will give you the required number.

Statement 2 doesn't tell you about the meals including other options hence it's not sufficient.

Answer (A)