Pollution Taxes Are More Efficient in Cleaning Up the Environment

Multiple Choice

Pollution taxes are more efficient in cleaning up the environment than direct controls.What role is there for direct controls?

A) They are useful standby mechanisms.
B) They are useful if it is decided to prohibit the substance altogether.
C) They are useful where dependable metering devices are not available or prohibitively costly to install.
D) All of the above are true.