The production function feature called constant returns to scale means that if we:
A.
multiply capital by z1 and labor by z2 , we multiply output by z3
B.
increase capital and labor by 10 percent each, we increase output by 10 percent.
C.
increase capital and labor by 5 percent each, we increase output by 10 percent.
D.
increase capital by 10 percent and increase labor by 5 percent, we increase output by 7.5 percent