1. Read & understand the passage...
2. Identify conclusion, facts , assumption as per requirement...
3. Do a bit of pre thinking, check relation of Bold phase with conclusion

I am confused between B & C. Can someone please elaborate? Does the reasoning offered by the librarian mention Harry and Ron's behaviour?

what is the author's opinion here? That would be the main conclusion of the argument.

The author's opinion is that Harry's library privileges should also be suspended.
What reasons does the author give to support this opinion ?
the reason given is that - the damage was caused by Ron's sister, so the difference was not due to difference between their behaviors.

Terms such as 'although' indicate a contrast. so, what follows 'although' must go against the reason given above.
If you say although X happened, Y happened. Here X and Y do not reinforce each other. But X goes against Y.

since, it goes against the reason that supports the author's opinion, it probably is an objection to the argument's conclusion.

A - not correct. Notice that only the subordinate clause that follows 'although' is highlighted and not the main clause - which gives a reason to support the author's conclusion.
B - correct answer. The author responds to the object in the main clause that follows although.
C - incorrect. there is only one person who is making the argument. There is no mention of any person who opposes the author's view. (opponent).
D - this piece is very much relevant - It raises a possible objection to the author's conclusion.
E - Incorrect. The author addresses this objection. So, it does not disprove the author's opinion.

Hope this helps
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A. It provides evidence directly supporting the conclusion of the argument.( WRONG ANSWER : The bolded doesn’t provide any kind of support to the conclusion of the argument.)

B. It identifies a possible objection to the conclusion, to which the author then responds.( RIGHT ANSWER : This option correctly identifies the role played by the bolded statement. The bolded statement puts forward a possible objection to the conclusion but the author strongly refutes this possible objection in the statements written after the bolded statement.)

C. It summarizes the reasoning offered by an opponent of the argument.( WRONG ANSWER : The opponent’s view is not all present in the argument.)

D. It provides unrelated information not relevant to the argument.( WRONG ANSWER : The information provided in the boldface statement is in line with whatever is discussed in the argument.)

E. It provides information proving the falsity of the conclusion.( WRONG ANSWER : The bolded statement does no such thing.)
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