SAT Question 35e05e19: Nonlinear Functions answer and explanation with Desmos solution

Choice A is correct. The volume of a prism is equal to the area of its base times its height. It's given that the length of each house's base is $x$ inches and that this length is $1$ inch more than the width, in inches, of the house's base. It follows that the width, in inches, of the house's base is $x-1$. The area of a rectangle is the product of its length and its width. Therefore, the area of the base of the house is $x(x-1)$ square inches. It's given that the height of each house is $11$ inches. Therefore, the function $V$ that gives the volume of each house, in cubic inches, in terms of the length of the house's base $x$ is $V(x)=x(x-1)11$, or $V(x)=11x(x-1)$.