Under the Comprehensive Environmental Response, Compensation, and Liability Act $($CERCLA$),$ Joint and Several liability means:

A$.$ that any party responsible for any part of the contamination can be liable for $100$ percent of the cleanup costs; B$.$that the government is only allowed to collect from a party responsible for contamination in the party's proportionate share of fault

C$.$neither a nor b;

D$.$ both a and b