The correct answer would be the third one.
"It would benefit many people to learn how to help protect our environment."
It has a professional tones and uses grammatically correct words.
I hope this helped!
The correctly punctuated sentence is the first one "Will we ever get there?". It´s a direct question, so the question mark is obligatory at the end and it replaces a period in case the sentence finishes there.
The second part "Sandy asked fretfully", must be preceded by a comma because what comes after is the person who came up with the question. However, if it is a quoted question (it doesn´t seem to be the case here), which end in mid sentence, the question mark replaces a comma.
Answer:
Candy was very harsh towards the other outcast in Mice and men
Explanation: