This diagram shows a photograph (shaded) mounted on cardboard.

The cardboard measures 100 mm by 150 mm, and the boarder around the photograph is a uniform x mm wide.

Which is the expression (in mm) for the area of the photograph.

A 150 x 100 - 150x -100x

B 100 x 150 - 4x^ (this is meant to be 2 squared)

C 100 x150 - 4x

D (100 + 2x)(150+2x)

E (100 - 2x)(150 - 2x)