Directions: This question presents a sentence, all or part of which is underlined. Beneath the sentence you will find five ways of phrasing the underlined part. The first of these repeats the original; the other four are different. If you think the original is best, choose the first answer; otherwise choose one of the others.

To all of them who have liberally given their advice and suggestions in response to requests from Professor Morgan, it is impossible for me to make adequate acknowledgment.

To all of them who have liberally given their advice and suggestions in response to requests from Professor Morgan,

They who have liberally given their advice and suggestions in response to requests from Professor Morgan,

To all of those who have liberally given their advice and suggestions in response to requests from Professor Morgan,

In response to his requests, Professor Morgan has received liberally their advice and suggestions, but

To those who have liberally given their advice and suggestions in response to requests from Professor Morgan,