The pages of a book are numbered $1, 2, 3, 4, 5$, and so on. The digit $5$ appears exactly $16$ times. What is the maximum number of pages this book could have? (2019 Math Kangaroo Problem, Level 3-4, Question \#19) 
选项为:A:$$49$$  B:$$64$$  C:$$66$$  D:$$74$$  E:$$80$$  请回答其中一个选项.