Which of the following is false about a production isoquant: Select one:

a. Each point on an isoquant is technically efficient; that is, for each combination on the isoquant, the maximum possible output is that associated with the given isoquant.

b. Production isoquants' construction requires the price of labor and price of capital data

c. The concept of an isoquant implies that it is possible to substitute some amount of one input for some of the other, say, labor for capital while keeping output constant.

d. An isoquant is a curve showing all possible combinations of the inputs physically capable of producing a given (fixed) level of output.