Sentence Correction

ankit0703 wrote:While large banks can afford to maintain their own data-processing operations, many smaller regional and community banks are finding that the costs associated with upgrading data-processing equipment and with the development and maintenance of new products and technical staff are prohibitive.

In the above sentence how the two bold parts are parallel to each other?

Thanks in Advance.

you are forgetting one of the most important (and most obvious) features of official SC problems, which is that they have multiple choices.
your job is not to formulate "ideal" parallelism!
all you have to do is pick the choice with the BEST parallelism.

this is really important -- and it's really good news, too, since it's much easier to pick out the choice that's most parallel, out of a bunch of concrete options, than it is to create some sort of ideally worded sentence. (in fact, it's easier to make comparative judgments than to make absolute judgments about, well, just about anything. for instance, think of how easy it is to say which of two people is more attractive, vs. how hard it is to create some sort of absolute evaluation of human beauty.)

so, the issue here isn't, "is this ideal?" instead, the issue is "which of the choices is best?"
by taking the answer choices out of the picture, you are creating a task that is (unnecessarily) a million zillion thousand times harder than it has to be.

--

as just one example of many, consider #50 in the DIAGNOSTIC section of the OG (not the regular sentence correction section). i can't reproduce that content here, but it contains a parallel structure that's a lot like this one:
We argue just as often and about the same things as the couple next door.
--> here, the parallel structures are "just as often" and "about the same things".
are these exactly the same? well, no; one of them contains an actual adverb, while the other is a prep phrase that acts as an adverb.
but,
1/ this is as good as it's going to get -- there's no decent prep phrase that means "just as often", and there's also no adverb that means "about the same things"
and, more importantly,
2/ there's no better option.

don't make your job any harder than it needs to be! this is already hard enough, i'd say.

ankit0703 wrote:But "upgrading data-processing equipment" is a simple gerund phrase. How can this be parallel to "the development and maintenance of new products and technical staff"?

... because, well, it can.
see og12 #64 for another example in which the same thing happens.

again, the most important thing to say here -- really, the only thing worth saying here -- is that you should make comparative decisions about this stuff. you have five answer choices; they are your friends. if you are not actually asked to make a comparative decision about this stuff, then don't bother.

ankit0703 wrote:I was just expecting that this part of the sentence should be ideal.

never forget -- there are multiple-choice options for a reason!