During the first one hundred fifty years of the existence of this republic, no one expected the press was fair; newspapers were mostly shrill, scurrilous, and partisan.

in the sentence above we have two alternatives:
1st alter.) two clauses - No one (subject) expected (verb) + the press (subject) was (verb) fair. Proposed solution here is to disallow the run on sentence mistake --> No one expected that (sub-clause connector) the press would be fair

2nd alter.) one clause - No one expected the press to be fair

Concept building --> to be is an infinitive form of verb 'be'. All infinitive forms following the noun (noun phrase) serve as adjectives in the sentence. E.g. The students(noun) to go (infinitive form of verb, 'go')mad after failing GMAT risk little improvements in the future retakes.

ccassel wrote:How would you explain the answer to this question?

During the first one hundred fifty years of the existence of this republic, no one expected the press was fair; newspapers were mostly shrill, scurrilous, and partisan.

A. was
B. to be
C. of being
D. should be
E. had to be

Answer B

Expected X to be Y is the correct idiom..

During the first one hundred fifty years of the existence of this republic, no one expected the press was fair; newspapers were mostly shrill, scurrilous, and partisan.

Just a different way to attack this question.. we are talking about "during certain period..no one expected something". In this case Exception can't be in past tense.
So "Was" , "should be" & "had to be" completely out of question.
Being all most always wrong .. SO that leaves B.

Simple way already addressed by Atul.

B! Correct Idiomatic usage