Which of the Following Profit Functions Exhibits a Cobb-Douglas Production $\pi$

Multiple Choice

Which of the following profit functions exhibits a Cobb-Douglas production function?

A) $\pi$ = P x K^0.75L^0.50 - 20L - 35K.
B) $\pi$ = P x min(2L, 5K) - 20L - 35K.
C) $\pi$ = P x (3K + 4L) - 20L - 35K.
D) $\pi$ = P x (3K^0.5 + 4L^0.5) ^1/0.2 - 20L - 35K.