Most vaccines are derived from weakened or killed strains of

Most vaccines are derived from weakened or killed strains of the same virus that they prevent, unlike the derivation of smallpox vaccine from a different virus altogether.

(A) the derivation of smallpox vaccine from a different virus altogether

(B) smallpox vaccine, which is derived from a different virus altogether

(C) smallpox's vaccine, which gets derived from a different virus altogether

(D) when smallpox vaccine is derived from an altogether different virus

(E) the altogether different virus from which smallpox vaccine is derived

Unlike is always followed by a noun,so we can short list B and C, C is in correct because --smallpox's vaccine, which gets derived-- Vaccine dosent gets derived itself.

"Vaccine of smallpox" is right to use; thus, smallpox's vaccine is not wrong.

Actual problem in C is use of "gets" in the passive construction.
In passive construction we are allowed to use "to be" form of verb as used in option B.
is derived (correct)
gets derived (wrong)

Refer chapter 7, MGMAT SC guide, Active and Passive voice.

Can anyone pls help me differentiate between option B and C.

Thanks in advance.

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Most vaccines are derived from weakened or killed strains of the same virus that they prevent, unlike the derivation of smallpox vaccine from a different virus altogether.


(B) smallpox vaccine, which is derived from a different virus altogether

(C) smallpox's vaccine, which gets derived from a different virus altogether

Hi,
here 'most vaccines' are compared with 'smallpox vaccines' .

1.smallpox's vaccines is same as 'vaccines of smallpox' , which is in passive voice therefore not parallel to 'most vaccines'.
2. Here the modifier contains a fact and should be written in simple form. In option C , the modifier is in passive voice ( which is not better than Active in this ques). As per Manhattan Sc 'Do not use other verbs besides 'be', such as get, to form the passive voice'.

Hi experts.

smallpox vaccines in choice B seems to be compared with most vaccines,the subject of the sentence.

My question is:

Can the word "unlike" after comma be used to compare with the subject of the sentence, which is really far away from the word "unlike" ?

In my opinion, it would be better if "unlike ... "clause were placed before the main sentence.

Please correct me if I'm wrong.

Thank you.

When you're evaluating the usage of "unlike" there are only two factors to consider: 1) is "unlike" used to compare nouns or noun phrases? and 2) is the comparison logical?

If both criteria are met, it doesn't matter if the elements are far apart, or if the construction is "X, unlike Y," as opposed to "unlike X, Y." In this case, every option has the X, unlike Y construction, so there's no reason to exert any mental energy considering whether another construction might be better! In general, once you satisfy that you're looking at a logical comparison, you want to move on to other decision points.

I hope that helps!

Here "Most vaccines" is being compared with smallpox vaccine.
B is the clear winner.

why "get derived" is wrong?

I think "get derived" means the vaccines actively get something done.
'I get my hair cut" means I actively have my hair cut by somesone.

but vaccine can not actively do something, so, the sentence is not logic

am I right? I am not confident of this point

Though its an old thread, hopefully my response helps someone.

(B) smallpox vaccine, which is derived from a different virus altogether - smallpox acts as an adjective modifying vaccine. Ask yourself, what type of vaccine? Smallpox vaccine.
(C) smallpox's vaccine, which gets derived from a different virus altogether - Usage of smallpox's indicates that vaccine belongs to smallpox. That is wrong.

Also, the usage of gets indicate that the activity of getting is automatic.

See the difference -

The work gets done.
The work is done (by whom?)

Thanks

(A) the derivation of smallpox vaccine from a different virus altogether

1) a wrong comparison: "unlike" is used to compare nouns, nouns that are logical to compare. "unlike" can be placed differently:

1) Unlike men, women have to devote most of their time to their children.
2) women,Unlike men, have to devote most of their time to their children.
3) women have to devote most of their time to their children,Unlike men.

all three have the same meaning although "unlike" is placed differently.
answer choice (A) uses the same structure as the third example does. Yet, "Most vaccines" are being compared with "the derivation"

(B) smallpox vaccine, which is derived from a different virus altogether

1) A logical and correct comparison: "most vaccines" are compared with "smallbox vaccine". So, let's keep B.


(C) smallpox's vaccine, which gets derived from a different virus altogether

1) "smallbox" works better than "smallbox's vaccine": smallbox has a vaccine?
2) "which is derived from" is better than "which gets derived from": In basic grammar, "get + V_ed" can sometimes substitute for "to be + V_ed" as a passive voice indicator, but the latter gives the logical and total passive voice better.

(D) when smallpox vaccine is derived from an altogether different virus

1) illogical meaning: this choice does not use comparison anymore, but use "when", meaning that when, or at the same time , smallbox vaccine is derived from different virus, then most vaccines are derived from weakened or killed strains of the same virus.

2) a wrong comparison: "most vaccines" are compared with "when + clause", which is an adverbial phrase.

(E) the altogether different virus from which smallpox vaccine is derived[/quote]

1) a wrong comparison: "most vaccines" are compared with "virus".

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