Sentence Correction

The Chief Executive Officer met with the Board of Directors to consider the possibility of a hostile takeover attempt by a competitor and how they would have to respond to deal with them.
a. how they would have to respond to deal with them
b. how to deal with them if action would become necessary
c. what action would be required for dealing with such an event
d. what action would be necessary to deal with such an event
e. the necessity of taking action in order to deal with it

The answer is d. I want to know how its parallel

Hi Palak

The question is of the form: to consider A and B. The 'A' here is a noun phrase: the possibility of a hostile takeover. Therefore, 'B' should be a noun phrase as well. Options A and B have a problem with pronoun 'them'. Option E changes the meaning of the sentence. Between C and D, D is correct since 'necessary to deal with' is idiomatically correct.

Just to highlight, while practicing, you would see few questions based on similar concept around adverb phrases starting with 'how'. Example -> The company X is considering how to do A and how to achieve B. Both elements here have adverbial properties. You can deal with such questions quickly by recognizing this pattern

Hope that clarifies.