Sentence Correction

While larger banks can afford to maintain their own data-processing operations, many smaller regional and community banks are finding that the cost associated with upgrading data-processing equipment and with the development and maintenance of new products and technical staff are prohibitive.

A. cost associated with

B. costs associated with

C. costs arising from

D. cost of

E. costs of

daretodream wrote:While larger banks can afford to maintain their own data-processing operations, many smaller regional and community banks are finding that the cost associated with upgrading data-processing equipment and with the development and maintenance of new products and technical staff are prohibitive.

A. cost associated with
s-v disagreement

B. costs associated with

C. costs arising from
Awkward.

D. cost of
s-v disagreement

E. costs of
Awkward construction.

IMO B. The plural verb in the non-underlined portion requires a plural subject.

daretodream wrote:While larger banks can afford to maintain their own data-processing operations, many smaller regional and community banks are finding that the cost associated with upgrading data-processing equipment and with the development and maintenance of new products and technical staff are prohibitive.

A. cost associated with

B. costs associated with

C. costs arising from

D. cost of

E. costs of

B is the best choice - maintaining parallelism (costs associated with....and with) and subject verb agreement (....costs....are....)

A, D - incorrect - subject (costs) needs to be plural because of the plural verb "are prohibitive "

C, E - violating parallelism

cost is acting as a noun here and not verb. So, to agree with the verb are prohibitive it has to be costs. Rest all is parallelism.

Check out below link,
https://www.beatthegmat.com/cost-vs-costs-t8909.html