I ALWAYS KEEP THE WINDOW OPEN __________ LET FRESH AIR IN ....

Question

3/ I always keep the window open __________ let fresh air in .         A. so as       B. order to      C. in order to       D. so that

Answer

3/ I always keep the window open __________ let fresh air in .         A. so as       B. order to      C. in order to       D. so that