Every year many people become ill because of airborne mold

[RonPurewal]

I mean, In choice A, although mold create moisture, the moisture will not be a problem because we keep plumbing in good condition anytime.

^^ if mold can CREATE moisture -- BY ITSELF -- then plumbing becomes irrelevant.
under those circumstances, mold could create moisture ANYWHERE -- so, there would no longer be a reason to focus on plumbing / water lines in particular.

[RonPurewal]

And If I have to think in the way that " you don't have to know whether it is in good condition. You can find an expert to help you."

^^ this is just everyday common-sense thinking.

for instance, most people have no idea how to inspect their car's engines, but i can still give useful advice such as "...be sure to keep your car's engine in good running condition."
obviously, most people would have to take their cars to a mechanic to DETERMINE whether the engines were "in good running condition" (and also to perform any required maintenance) -- but, that's just simple common sense.

everyday common-sense thinking is ALWAYS in-bounds on these problems.

[JbhB682]

I eliminated the OA (A) unfortunately -- Here was my reasoning for eliminating A


The author just says "If one wishes to avoid mold poisoning...one should make sure to keep all internal plumbing in good condition to prevent leakage" that could serve as a breeding ground for mold.

To me it sounds as if the author proposes that keeping plumbing good is JUST ONE WAY to avoid moisture and thus avoid mold poisoning (there are other things in the house that generate moisture)

The author in his final conclusion is NOT saying, Plumbing is ONLY source of moisture because of the word "COULD SERVE as a breeding ground..."


Maybe moisture from plumbing makes up 95% of the cases.

If Plumbing only serves as 95 % of the cases where moisture builds up in the house, then why does it matter if "Mold itself does not create moisture."

In my pre-thinking -- I was looking for something like

--- More proof that plumbing DOES create moisture

[esledge]

To me it sounds as if the author proposes that keeping plumbing good is JUST ONE WAY to avoid moisture and thus avoid mold poisoning (there are other things in the house that generate moisture)

Yep, other things could cause moisture! (Such as the mold itself, per choice A)
And if there are multiple ways to cause/avoid moisture, the argument that just preventing ONE of them (“prevent leakage”) is enough to “avoid mold poisoning” is weak.
It is necessary to rule out or dismiss (an)other way to cause/avoid moisture.
-----
This is another example of how the Negation Test really helps. Negation of (A): Mold itself DOES cause moisture.
If that’s so, specialists look for moisture because it’s the sign of mold, not the cause of it. Thus, preventing leaks wouldn’t (necessarily) fix/prevent mold in the first place. The conclusion suffers, telling us that (A) is necessary.

In my pre-thinking -- I was looking for something like

--- More proof that plumbing DOES create moisture

You didn’t say what choice you did pick. Was it (B), because it at least mentioned "plumbing"? If so, (B) doesn't exactly say what you were looking for anyway, and the negation test will really prove it wrong.

Negate (B): Some (a few) homeowners know enough about plumbing to determine whether theirs is in good condition.
Great! The conclusion (strictly: “If one wishes to avoid mold poisoning, … prevent (plumbing) leakage that could serve as a breeding ground for mold”) can still be ok. Thus, in it's non-negated form, (B) is not necessary.