Tough and Tricky questions: Geometry.

A Persian rug set on a dining room floor measures a inches by b inches, which includes the actual rug design and a solid colored border c inches. Which algebraic expression below represents the area of the solid colored border in square inches?

A) ab − 4c
B) a + b − [(a − c) + (b − c)]
C) 2a + 2b − [2(a − 2c) + 2(b − 2c)]
D) ab − (a − c)(b − c)
E) ab − (a − 2c)(b − 2c)

Kudos for a correct solution.

Source: Chili Hot GMAT
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