Question

i - ready and biking. no cars are allowed. these routes were made for trains many years ago. once the rails are removed, the paths are perfect for bicycles. you can ride these
ail trails\ through cities and from one city to another. the longest rail trail, in missouri, is 225 miles long! a cyclist travels across an old railroad bridge on a rail trail. fill in the blanks to explain why the author thinks rail trails are good for bikers. rail trails are safe because they let bikers avoid city streets. the trails are built on old routes that trains no longer use. so, bikers can ride for miles without coming near other bikes busy streets many people

Explanation:

The text says rail trails let bikers avoid city streets, so the last blank should be about what they avoid. The options are other bikes, busy streets, or many people. Since avoiding city streets means avoiding busy streets (as city streets are busy), "busy streets" is the correct choice.

Answer:

busy streets