The correct response is:
The constant of proportionality is 7. It takes the crew of workers 7 weeks to complete 1 road project.
In the equation \( y = 7x \), \( y \) represents the number of weeks required to complete the projects, and \( x \) represents the number of projects. The constant of proportionality (7 in this case) indicates that for each road project, it takes 7 weeks to complete it.