to find the surface area of figure we add all the areas of all faces
So Surface Area of figure = Area of large side rectangles + Area of small sides rectangles + Area of top and bottom rectangles
hence
Surface Area of figure = 2(20*15) + 2(7*20) +2(7*15)
= 2(300) + 2(140) + 2(105)
=600+280+210
= 1090 square inches
Option Third is the correct one