Solution:
Let the regular price of a product at store L be x and at store M be y.
First consider statement (1) alone.
At store L the discount price is x - 10%*x = 90%*x.
At store M the discount price is y - 15%*y = 85%*y.
We need to compare 90%*x and 85%*y.
More information is needed.
So (1) alone is not sufficient.

Next consider (2) alone.
At store L the discount price is x - 5.
At store M the discount price is y - 6.
We need to compare x - 5 and y - 6.
More information is required.
So (2) alone is not sufficient.

Next combine both the statements together and check.
We have then 90%*x = x - 5.
Or 5 = 10%*x.
Or x = 50.
Or discount price at L is 50 - 5 = 45.
Also 85%*y = y - 6.
Or 15%*y = 6.
Or y is 40.
Or discount price at M is 40 - 6 = 34.
Since 34 < 45, discount price at M is less than discount price at L.

The correct answer is hence (C).

Yes. It is talking about the price after discount.