In this case you want the area of a square ABCD. Well, look at the information that you are given. The triangle on the left has sides of the square root of 2. Well, that means that it's an isosceles triangle, so the hypotenuse is equal to a side times the square root of two. So we'd have the square root of 2 times the square root of 2. Then we have another isosceles triangle across the top, and it says its hypotenuse is the square root of 2. Well we know that each of the sides in this triangle must be 1. So we can easily see we've got a square ABCD that has sides of 1, so it has an area of 1, which is less than the square root of 2, so the answer is B.