Eco-travel is a form of travel ____ combines normal tourism with learning—a way to find out

　 what can be done to help animals, plants and people ____.

　 A. what; as well B. that; as well　　 C. that; as well　　 D. that; as well as

 We know that eco-travel is a form of travel combining common tourism with learning, ________ a way to find out what can be done to help animals, plants and people.

—________. 

A. as well as; I couldn’t agree any more            B. as far as; I disagree               

C. as soon as; I agree                           D. as long as; I don’t agree