Answer:
Yes, the answer is faulty.
Step-by-step explanation:
In order for the parallel structure to be complete you should try dividing the sentence in this way.
-The schools not only were closed
- because of the snow and ice,
- but, also
- because of the lack of heat and water (for example)
The parts that begin with because should contain the same structure, in this case two nouns divided by and.