Mark the letter A, B, G, or D to indicate the correct answer to each of the following questions. ( LÀM VÀ GIẢI THÍCH GIÚP TỚ

Mark the letter A, B, G, or D to indicate the correct answer to each of the following questions. ( LÀM VÀ GIẢI THÍCH GIÚP TỚ VỚI )
1. New York has invested substantially in improving the ____ of its waterways in recent years.
A. quality
B. quantity
C. level
D. feature
2. ____ there are some more ideas, we can end the meeting now.
A. Unless
B. If
C. As if
D. In case
3. I think the cities of tomorrow also need to consider the availability of open space, ____?
A. do I
B. don’t I
C. do they
D. don’t they