Mark the letter A, B, C or D on your answer sheet to indicate the correct answer that best completes each unfinished sentence, substitutes the underlined part, or has a close meaning to the original one
Trả lời câu hỏi dưới đây:
Carbon dioxide may be absorbed by trees or water bodies, or it may stay in the atmosphere when _______ while it is only in the atmosphere that chlorofluorocarbons find their home.