The per cent that represents the unshaded region in the figure.

Given, total parts = 10 × 10 = 100

Shaded parts = 60

⇒ Percent of shaded parts = × 100%

= 60

Then, percent of unshaded parts = 100-60 = 40

∴ unshaded region is 40%

⇒ Option A is incorrect as 75 ≠ 40

⇒ Option B is incorrect as 50 ≠ 40

⇒ Option C is correct as 40 = 40

⇒ Option D is incorrect as 48 ≠ 36