Himanshuv0

Yeah, that OG explanation is not very good. The team that writes the explanations is clearly not on the same level as the team that produces the questions.

Since B and D have other flaws, it’s not necessary that the -ing modifier be incorrect. “Fake” splits are common in SC! The -ing modifier makes a fair amount of sense here, but it does create a slight difference in meaning. The noun modifier in A/C/E tells us that cowpox causes a mild infection in general. So the idea is that we can infect someone with cowpox (not so bad) to prevent smallpox (a worse disease). Since B/D uses an adverbial modifier, these sentences are saying that the act of infecting someone deliberately with cowpox causes only a mild infection. This leaves open whether this is true of all cases of cowpox, or only those resulting from deliberate infection. That’s not a huge flaw in B/D, but I believe that’s what the OG explanation is trying to address.
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GMATNinja

Why is which caused correct in option E- Shouldnt it be, causes. My thought process is: It is a fact, and for facts simple present is used. Thanks

So we can use if and would together in a conditional statement?

Oh yes, in fact, very regularly.

Our book EducationAisle Sentence Correction Nirvana discusses Conditional statements, their application and examples in significant detail. If you or someone is interested, PM me your email-id; I can mail the corresponding section.
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I have a hardcopy of your book, can you please tell me the page numbers?

Thanks for trusting our book, for your GMAT Prep.

Conditional Constructs are covered in Chapter 7 (Tense and Subjunctive) in the sub-section titled "Conditional Constructs".
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Interesting question!

I'd say either tense is fine. You could write that cowpox causes a mild illness, in general. And you could also write that when certain people were infected with cowpox, the infection caused a mild illness, since the infections occurred in the past.

The upshot: if either construction could be justified, move on the other decision points! Fortunately, there are four nice concrete errors in this one, so there's no reason to agonize over the present vs. past tense decision.

I hope that clears things up!
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if experimental subjects were deliberately infected with cowpox... here the verb is not in simple past tense. So how can we deduce to use If..Then here?

Hello AbhiR3,

We hope this finds you well.

To resolve your query, we would like to point out that "were...infected" is indeed a simple past tense verb.

We hope this helps.
All the best!
Experts' Global Team
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The verb "were infected" is in fact considered simple past. Note that it's a passive verb: some unknown experimenters infected the subjects with small pox, and the subjects were infected by those experimenters.

Since the experimental subjects were acted on by the verb, we need to use the passive voice. And "was/were + past participle" is the correct form for the passive simple past.

I hope that helps!
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EducationAisle
Can you throw some light on options B and D.
Why is ,causing wrong here?
Not able to understand the solutions above.

Thanks

Hello krndatta,

We hope this finds you well.

Having gone through the question and your query, we believe we can resolve your doubt.

The use of "causing" slightly alters the meaning of the sentence, due to the use of the "comma + present participle ("verb+ing" - "causing" in this case)" construction; please remember, the introduction of the present participle ("verb+ing"- “causing” in this case) after comma generally leads to a cause-effect relationship.

The intended core meaning is that if experimental subjects were deliberately infected with cowpox, they would become immune to smallpox, and as extra information, it is also mentioned that cowpox causes only a mild illness.

The use of the "comma + present participle", however, implies that if experimental subjects were deliberately infected with cowpox, and doing so caused only a mild illness, they would become immune to smallpox.

We hope this helps.
All the best!
Experts' Global Team
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Hi krndatta, "present participial" phrase (causing...in this case) preceded by a comma, generally modifies the subject of the preceding clause.

In this case, the subject of the preceding clause is experimental subjects. Hence, B and D convey the sub-optimal meaning that experimental subjects caused only a mild illness (while as per the intended meaning, "cowpox" caused only a mild illness).

Following construct would be better (though would slightly change the meaning):

if cowpox were deliberately injected into experimental subjects, causing only a mild illness...

p.s. Our book EducationAisle Sentence Correction Nirvana discusses "present participial phrases", their application and examples in significant detail. If you or someone is interested, PM me your email-id; I can mail the corresponding section.
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