Latin America has no single dominant Spanish dialect: the range of Spa

OFFICIAL EXPLANATION



THE PROMPT

This question is kinda beastly.
Each is singular 99% of the time.
→ Each of the players wears a different number.
In this setup, each is a determiner. More on that subject below -- mentioned in NOTES.

But if each follows a plural subject such as the players or they, then each is a pronoun and is plural.
→ The players each wear a different number.
They each wear a different number.

This question lures you into the "each is ONLY singular" trap.

TAKEAWAYS
• when EACH comes before the subject, even if the target is plural, EACH is always singular:
Each Spanish dialect [is] a product of XYZ.

• we do not use the determiner each before plural nouns such as products.
(We could say "each of the dialects." But we are not given that option.)
See my Notes, below, in which I link two posts about the word "each."

• BUT if each comes after the subject or noun, then each can be plural if the noun is plural.
→ They each wear a different number.

THE OPTIONS


• each = singular dialect whose pronoun should be its, not their.
→ each = each of the dialects

• with is unnecessary. And weird.
→ what is with doing in this sentence? Answer: nothing logical. Buh-bye.
ELIMINATE A


• each products is babble
→ each is singular. Products is plural.
→ as a determiner (before the noun), each is always singular and cannot be paired with plural products.
→ There is no such thing as each products.
OK: Each product
OK: Each of the products
WRONG: Each products.

• wrong pronoun (their)
→ each, singular, should not be paired with their, plural.
→ Their should be its.
ELIMINATE B

• same problem as that in B: each products is babble
ELIMINATE C


• as in option A, the word with adds nothing to this sentence exception confusion
• the word as is not necessary.
KEEP, but hope that E is better.


• bingo
• each a product of its [local influences] is an appositive that defines, elaborates on, or defines the noun dialects
→ most appositives consist of [noun] + [noun modifiers]
noun here = each
noun modifiers = a product of

•This answer is better than answer D.
→ In D, with and as are unnecessary. Eliminate D.

The correct answer is E.

NOTES

For a fun (but hard) question to which my "each" posts are attached, see this thread, by clicking here.

I describe and explain the usage of each in two posts on that thread.
→ One of the EACH posts is here (click)..
→ The other EACH post is here.
Those posts should help.

COMMENTS

This question tests an issue that a person just has to learn about somewhere: how each works.

GMAC uses "each" quite often.

chillbrorelax , amit2100 , and SairamRamo , welcome to SC Butler (probably your second welcome today).

I am impressed with the quality, depth, and range of nearly all of these answers.
Aspirants should read this thread.
The more ways in which you are exposed to ideas, the more likely you are to learn and remember them.
(Unless the subject is golf and the student is yours truly. I compete in other sports in which putting—the ninth level of hell, see Dante—is not involved.)

I am very glad to see people taking risks, such as adding humor to posts, changing the way that they explain concepts, or even posting at all.
My standing invitation to all aspirants to post still stands.

Really nice work. Be safe.