Market$-$oriented environmental policies are$\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_,$ and$\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$will work better in some situations than in others.

Question $14$ options:

a tool$-$kit; specific tools

productive policies; some policies

inflexible; incentives to protect endangered species

flexible; the command$-$and$-$control approach