Decreasing returns to scale may arise from ______.A．specialization of inputs.B．duplication

Decreasing returns to scale may arise from ______.

A．specialization of inputs.

B．duplication of plant and equipment at equal cost.

C．inefficiencies in management.

D．using inputs in unequal proportions.

请帮忙给出正确答案和分析，谢谢！