Luke is planning to lay two decorative pieces of wood across the 12-inch by 24-inch rectangular glass centerpiece of a cabinet. each piece will lie on a diagonal of the centerpiece. select a number from the drop down menu to correctly complete the statement. each piece of wood should have a length of approximately how many inches.

What you are looking for is the hypotenuse of a right triangle.
If you have a 12 x 24 rectangle, these would be the sides of the triangle and we would use Pythagorean Theorem to find the hypotenuse.
a^2 + b^2 = c^2
12^2 + 24^2 = c^2
144 + 576 = c^2
720 = c^2
take the square root of both sides
c = sqrt(720)
c = 26.8 inches is the approximate answer.
I don't know what your choices are but one should be close to this answer.