With more and more classes being offered online, more and more student

It's B because online courses DO offer the ability to attend class (in this context this means that you can redo stuff etc.) outside of regular class hours. Therefore this is a strengthener to the argument. All others weaken the position.

We have to find which one is NOT an objection -
a. online courses are more time consuming for faculty to develop than regular courses.-This is objection to idea of online courses.
b. many students need the ability to attend class outside of regular classroom hours. - This supports idea of having online courses . That's why this is answer.
c. some students prefer the traditional classroom to the virtual classroom.-This is objection to idea of online courses.
d. not every course is suitable for an online environment.-This is objection to idea of online courses.- -This is objection to idea of online courses.
e. there is no way to ensure the authenticity of a student’s work in an online environment.-This is objection to idea of online courses.

E is not answer as it objects online courses. We have to find which is NOT a valid objection.

It is super easy question since no critical trap is present. It is except weaken question ;so four answers will weaken and only one answer would either strengthen or beyond the topic.
We can test every option by the following template:
They should not invest online because....
A,C,D,E fits very well in the above template so they all weaken the argument. But B doesn't fit,so odd one out!

The answer is obviously B, but this is not a great question. At the very least, the question stem needs to be revised.

The question stem asks what is not a "valid objection" to investing the bulk of resources into developing online degree programs. A valid objection is not one that casts a little doubt - it is much stronger than that. Notice that the argument does not say that all resources should be invested into online programs, just that the "bulk" should be. This is a very important distinction from a logical perspective, because having some students prefer traditional settings (C) and having some courses more suitable for in-person (D) offers a small amount of support for keeping traditional classes but does not argue against still investing the bulk of resources into online degree programs. If you don't agree, consider that we could invest 80 percent of resources into online programs (certainly qualifies as the bulk) and still put 20 percent of resources into in-person classes to satisfy the "some" students who prefer that and to make sure that the few courses that are not suitable for online delivery ("not every" only guarantees at least one exception) can still be in person.

Even (A) might not be a valid objection. Sure, it might take more resources, but it doesn't say how much more (could only be slightly more), and there could be other reasons why that is perfectly okay. If the demand is there, then investing more time might still be worth the returns as long as each course is even slightly more profitable than the alternative of having in-person classes. This casts some doubt, but it is not a valid objection.

C and D (and probably A) do not offer valid objections to the argument. While B is obviously the intended answer because it strengthens the argument, the question stem as written is compatible with multiple answers and should be rewritten. A better question stem would be something closer to "Each of the following, if true, casts doubt on the argument EXCEPT" because that doesn't force each incorrect answer to be a valid objection.

I'm not sure why these Knewton questions keep popping up as QOTD, but they are prone to having issues, just like most other non-official verbal questions. It's best to stick to ones from GMAC if possible.

Official Explanation

Correct Answer: B

All of the choices except b offer reasons why online degree programs are problematic, suggesting that resources should not be focused on developing online degree programs. Choice b offers support for the argument by stating that the flexibility of online classes will attract students who would not normally be able to attend regular classes.

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