In my opinion, the fastest approach here is to test the answer choices (which I'll leave to you)

Alternatively, here's an algebraic solution.

Let G = Gretel's age
So, G + 7 = Hansel's age

Since the product of their ages is 60, we can write: (G)(G + 7) = 60
Expand: G² + 7G = 60
Since we have a quadratic equation, we'll set it equal to zero by subtracting 60 from both sides: G² + 7G - 60 = 0
Factor to get: (G + 12)(G - 5) = 0
So, either G = -12 or G = 5

Since Gretel's age can't be negative, we know that battle must be 5 years old

Answer: A