The correct option is A 4, m + 2n - 3
Area of rectangle = Length × Width
Area of the door = 4m + 8n - 12
Common factor of the terms 4m, 8n, and -12 is 4.
Taking 4 common from both sides, we get,
4m + 8n - 12 = 4(m + 2n - 3)
Hence, the dimensions of the door are 4, (m + 2n - 3)