Answer:
a) How often
Explanation:
Question says twice a week, so it is asking how often.
The Things They Carried.
This book is an incredible account of the Vietnam War that uses item (the things they carried) in an effort to describe how soldiers in the war went about their days.
Side note: A very good, short read.
Answer: C
Explanation: Most webpages giving info on a location have it in a Q&A style