Let a rectangle $$ABCD$$ of sides 2 and 4 be inscribed in another rectangle $$PQRS$$ such that the vertices of the rectangle $$ABCD$$ lie on the sides of the rectangle $$PQRS$$. Let $$a$$ and $$b$$ be the sides of the rectangle $$PQRS$$ when its area is maximum. Then $$(a + b)^2$$ is equal to :

A

72

B

60

C

64

D

80