Lack of Skilled Labor

IMO B
a. Although on the one hand it is true that the lack of computer-related skills accounts for and
explains many of the problems in today’s job market, there is meanwhile a lack of skilled labor in
many different fields. - Redundant "Although on the one hand"
b. While the lack of computer-related skills accounts for many of the problems in today’s job market, the lack of skilled labor is evident in many different fields. - Parallel
c. A lack of skilled labor affects all fields, not just computer-related, the problems in today’s job market shows. - awkward construction
d. While the lack of computer-related skills accounts for many of the problems in today’s job market, many different fields are also experiencing a shortage of skilled labor. - Not Parallel
e. Lacking computer-related skills, today’s job market has many problems, and other fields also lack
skilled labor - awkward construction

I think in the end we can narrow it down to B and D ....
then B wins as it is parallel and D isn't.

OA is D

I too went with B seeing that it is parallel, but the explanation given is as follows:

d. Choice a is wordy and redundant. Choice b is correct, but it is less effective than choice d because
the word choice and sentence structure are less sophisticated. Choice c has an error in subject-verb
agreement (problems . . . shows) and has awkward word order. Choice e has a misplaced modifier;
because of its placement, lacking computer-related skills modifies today’s job market.

Source: GMAT Exam Success in only 4 steps

Can the experts on the forum comment on this? The preference is given to Active Voice over Parallelism.

Could not agree with supposedly correct OA, experts please confirm. These kind of questions do shake up the concepts (reminds me of experts suggestion "check the source before checking the OA".

This was the only question from the given source that I have a doubt on; otherwise other questions were pretty much in sync with the concepts in other places. Even I am not very convinced with the explanation but do not want to lose on any concept here, if there is one.

Expert Help Needed!!!