B. Last year ...
1) Dusty and dirty. People there were talking loudly.
2) Very poor, there wasn't many books there.
3) Quiet and comfortable, with books about everything.
В тексте сказано: «Mark liked the library very much. There were flowers everywhere and it smelled nice and it was quiet so he could read the book in comfort.»
Ответ: 3) Quiet and comfortable, with books about everything.