Mark the letter A, B, C, or D on your answer sheet to indicate the cor

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.    

Wastewater is treated and turned into drinking water. This is done to ensure there is no shortage of fresh water.

• A. A. For there is shortage of fresh water, wastewater is treated and turned into drinking water.
• B. B. Wastewater is treated and turned into drinking water because there is shortage of fresh water.
• C. C. Wastewater is treated and turned into drinking water though there is no shortage of fresh water.
• D. D. To ensure there is no shortage of fresh water, wastewater is treated and turned into drinking water.

2 câu có mối quan hệ mục đích => D
A, B là mối quan hệ nguyên nhân - kết quả
C là mối quan hệ đối lập