Which of the following statements is true?

a)

Productive inefficiency implies that it is possible to produce more of one good and no less of another, but only if additional resources are made available.

b)

Productive inefficiency implies that it is possible to produce more of one good and no less of another, even without additional resources.

c)

Productive inefficiency implies that it is impossible to produce more of one good and no less of another.

d)

Productive efficiency implies that it is possible to produce more of one good and no less of another, even without additional resources.