I would say that the trait that distinguishes modern drama from traditional drama is A) the plot of modern drama does not always follow a strict structure and might end without a clear resolution.
The plays in the past would always be written according some strict rules, whereas today those rules aren't as important.
14 is water and although I made sure to look at the passage I knew that it was water anyway because water is not considered to be a living organism but it contains many different living organisms.
15 would be D
16 would be A
17 I am not entirely sure but I believe it is C
18 would be A
19 I am not entirely sure but I believe It is B
20 I would believe would be D
I hope I helped!
True, you should always be familiar with the text.