Before the Civil War, Harriet Tubman, along with other former slaves and white abolitionists, helped create what had become known as the Underground Railroad, and were responsible for leading hundreds, if not thousands, of slaves to freedom.
A. had become known as the Underground Railroad, and were
B. would become known as the Underground Railroad, and were
C. had become known as the Underground Railroad, and was
D. has been becoming known as the Underground Railroad, and was
E. would become known as the Underground Railroad, and was >>>
Stripping the sentence of the modifiers we get the sentence:
Harriet Tubman helped creat what ....... , and was responsible......
Singular subject , along with xxx needs singular verb : hence was
eliminate a,b
Options c, d ,e are contender
>>>
Meaning.
the usage of known should be logical
had become known: implies that it is known before it's creation
Past perfect(had) means the knowing is before helped(helped create)
Which is wrong
eliminate c
has been becoming known as : the effect of knowing has not completed , which is not the meaning
also this structure is redundant
eliminate d
So ANSWER IS E
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