Because the dependent clause beginning with "that" is modifying "a large number of communities," the verb should be PLURAL. Remember that in English, certain expressions with prepositions are considered plural:
- some of the people are...
- all of the ducks have...
- many of the robots want...
- a number of the communities are...
etc.
(A) is looking to its waterfront as a way to improve the quality of urban life and attract
- wrong verb: "is"
(B) is looking at its waterfront to improve the quality of urban life and attract
- wrong verb
- "looking at" doesn't work in this context. There is a meaning difference between "looking at something" and "looking to something in order for something to happen."
(C) are looking to their waterfronts to improve the quality of urban life and attract
- correct
(D) are looking to its waterfront as a way of improving the quality of urban life and attracting
- we can't use the singular pronoun "its" with the plural "communities"
(E) are looking at their waterfronts as a way they can improve the quality of urban life and attract
- "looking at" is wrong
- the meaning suggests that the act of looking at waterfronts itself is the thing that will improve urban life. This is nonsensical,
The answer is C.
Ceilidh Erickson
EdM in Mind, Brain, and Education
Harvard Graduate School of Education