Which one of the statements is correct?
- AIn the short run all factors of production are fixed; in the long run all factors are varied.
- BIn the short run at least one factor is fixed; in the long run all factors can be varied.
- CIn the short run at least one factor is varied; in the long run all factors are fixed.
- DIn the short run at least one factor is varied; in the long run at least one factor is fixed.