Question: Preoccupation with Celebrities

Yes that's fine. The phrase before it ""devoted to producing figurines and collector plates" is a vital noun modifier.

First answer: There aren't really cases when the verb should appear before the subject. It's more about the author's preferences. For example, we can also write "Out of Maltania's preoccupation with celebrities, a new industry has emerged...."

Second answer: That sounds fine.

Removing the fluff to recognize that we need the singular verb "has" sounds like a valid approach to me.

Great question, Itzel!

NOTE: This concept wouldn't be tested on the GMAT.

We don't have a comma, because the first word after the prepositional phrase ("Out of Maltania's .....trinkets") is the verb phrase HAVE EMERGED.

If, instead, the first word were a NOUN, a could use a comma. For example:
Out of Maltania's preoccupation with celebrities and trinkets, an INDUSTRY has emerged..."

As I said, you won't be tested on this. In fact, there's even disagreement among grammarians about how many words a prepositional phrase must have before it deserves a comma. For example, some say the phrase must have at least 5 words to deserve a comma (so, "AT NOON Joe ate lunch" would be fine for these people.

Does that help?

Cheers,
Brent

Good question.
Figurines and collector plates cannot perform the act of hiring.

Also notice that "devoted to producing figurines and collector plates" modifies the noun INDUSTRY.

Also, notice that, IF "figurines and collector plates" (plural) were the subject here, then then singular (IS) would not match.

Does that help?

Cheers,
Brent

Yes, the present tense IS HIRING is correct.

Although it may be the case that an industry is comprised of many companies, we still need the VERB to match the given SUBJECT.

Notice the many problems that would arise IF WE HAD to take the industries composition into consideration:

- For example, if the is comprised of MANY COMPANIES, and all of those companies hire employees then we'd say "The industry HIRE" to reflect the many companies within the industry.

- But, what if the industry is comprised of just ONE COMPANY, and that company hires employees?
Do we write: "The industry HIRES" to reflect the single company within the industry?

- Or, what if the industry is comprised of just MANY COMPANIES, but just ONE of those companies actually hires employees.
Do we write: "The industry HIRES" to reflect the ONE company that hires, or do we use HIRE?

So, if we go back to the original question, we can see that we'd need to know a lot more about this emerging company in order to determine whether to use HIRE or HIRES.

Does that help?

Cheers,
Brent

(A) Out of Maltania's preoccupation with celebrities and trinkets have emerged a new industry devoted to producing figurines and a collector's plates that are hiring hundreds of workers each month.

"with celebrities and trinkets" is a prepositional phrase modifying preoccupation. So we can ignore it for now.
Likewise, "devoted to producing figurines and a collector's plates" is a participial phrase modifying industry.
So we can ignore this is well.

Can we do this we get: Out of Maltania's preoccupation have emerged a new industry"
A new industry HAVE emerged?
No good.
ELIMINATE A and B

Does that help?