1. should
2. ought to
3. can
4. must
5. have to
6. may
I am like 95% sure these are the answers. Hope this helps! :)
The most accurate answer among the choices to complete the question is the fourth one (hanging indent). This refers to types of paragraphs in which only the second and succeeding lines are being indented.
Hope my answer has come to satisfy your query.
I think that its (b)
lol i just read this about a day ago
hope its right