Passage

The town's bicycle-sharing program has reduced short car trips, particularly near train stations. Expanding the program to other busy areas could therefore reduce traffic further.

Best Summary

Because bicycle sharing has reduced short car trips near stations, expanding it may further reduce traffic.

Solution

1. The first sentence is evidence about the existing program.
2. The second sentence draws the main conclusion about expansion.
3. The summary includes the evidence-conclusion relationship and preserves 'could' as a possibility.