Select the most appropriate option that can substitute the bold segment in the given sentence. If there is no need to substitute it, select ‘No substitution’.
Spreading awareness about the importance of environmental protection and the steps open to citizens in case they witness pollution has rightly been identified as the first priority.

The subject "steps" is plural, but here it is part of a compound subject along with "spreading awareness," which is singular. The verb should agree with the singular compound subject, so "is open" is correct as it agrees with the singular sense of "spreading awareness about ... and the steps..." treated collectively. Also, "open to citizens" is better expressed as "is open to citizens" to maintain grammatical correctness. Hence, option 4 is the most appropriate substitution.