A - weight which allowed - which refer to weight
B - weight, which allows - allows does not agree in number with homeotherms
C - Same as A - weight allows them to survive on far less food - wrong meaning
E - ING form without comma modifies the noun just before it - again the same error as above.

D seems fine.

Hope I am right Correct me if anything is wrong.

A) weight which allowed which always occurs with a comma because it is not restrictive.
B) weight, which allows Most students think which can modify only the nouns preceding it. its not true. which refers to verb expend over 70%
C) weight which has allowed no comma
D) weight that has been allowing no need for a restrictive that
E) weight allowing no comma. 'ing modifiers are preceded by a comma

patanjali.purpose wrote:Poikilotherms can subsist in what would be fatally food-depleted environments; they expend over 70% less energy than homeotherms per pound of body weight which allowed them to survive on far less food.

A) weight which allowed
B) weight, which allows
C) weight which has allowed
D) weight that has been allowing
E) weight allowing

IMO both B and E are correct - what you think?
GROCKIT; OA-B

B) weight, which allows Most students think which can modify only the nouns preceding it. its not true. which refers to verb expend over 70%

@GMAT Kolaveri - WHICH is a pronoun (it cannot refer to VERBS)

Made a mistake in posting OA; oa-B

But I do not find any difference btn B and D. Any view

There was an earthquake in China, which is bad news.

I'm not sure if which refers to the verb, but which usage is not restricted to noun alone. Thats what I heard from Payal from E-gmat.
May be the experts can help us in the question and correct usage of which. What all roles can "which" play in a sentence. Experts please help.

https://grammar.quickanddirtytips.com/wh ... -that.aspx

What is the subject of the verb 'allows' in B and what does which refer to in B ? ? Would be great if someone can explain.

sam2304 wrote:What is the subject of the verb 'allows' in B and what does which refer to in B ? ? Would be great if someone can explain.

IMO " per pound of body weight" is the subject of ALLOWS and therefore, think B and E are same

patanjali.purpose wrote:

sam2304 wrote:What is the subject of the verb 'allows' in B and what does which refer to in B ? ? Would be great if someone can explain.

IMO " per pound of body weight" is the subject of ALLOWS and therefore, think B and E are same

Isn't that a prepositional phrase ? Can it be a subject ?

Poikilotherms can subsist in what would be fatally food-depleted environments; they expend over 70% less energy than homeotherms per pound of body weight which allowed them to survive on far less food.

A) weight which allowed
B) weight, which allows
C) weight which has allowed
D) weight that has been allowing
E) weight allowing

There seems some problem in this question. Are you sure you typed the question properly ?

I think there should be comma in E - before "allowing". Can you please recheck it.

a relative clause is not apt - " allowed them to survive on far less food" cannot be an adjective here. It is the result of the clause : "they expend over 70% less energy than homeotherms per pound of body weight" ---->

they expend over 70% less energy than homeotherms per pound of body weight, allowing them...... --- perfect

avik.ch wrote:

Poikilotherms can subsist in what would be fatally food-depleted environments; they expend over 70% less energy than homeotherms per pound of body weight which allowed them to survive on far less food.

A) weight which allowed
B) weight, which allows
C) weight which has allowed
D) weight that has been allowing
E) weight allowing

There seems some problem in this question. Are you sure you typed the question properly ?

I think there should be comma in E - before "allowing". Can you please recheck it.

a relative clause is not apt - " allowed them to survive on far less food" cannot be an adjective here. It is the result of the clause : "they expend over 70% less energy than homeotherms per pound of body weight" ---->

they expend over 70% less energy than homeotherms per pound of body weight, allowing them...... --- perfect

B is the perfect.
What allowed them to survive? the act of expending over 70% less energy.
This is referred by "which" and is separated by comma. Comma is must when non-restrictive which is used.

Which can refer to clauses

GMAT Kolaveri wrote:
B is the perfect.
What allowed them to survive? the act of expending over 70% less energy.
This is referred by "which" and is separated by comma. Comma is must when non-restrictive which is used.

Which can refer to clauses

Yes, pronoun can refer to an noun clause. here "which" cannot refer to the action " they expend over 70% less energy than homeotherms per pound of body weight" for 2 reason,

1. a pronoun can refer to a noun clause only ( but there are no SC in OG where a pronoun stand for a preceding noun clause. If you have got any, please show me.) here "they expend over 70% less energy than homeotherms per pound of body weight " is not a noun clause.

Moreover, "which" is a relative pronoun.
When we modify a noun clause, being a clause, we need an adverb. Relative pronoun cannot introduce a adverbial modifier.


2. GMAT has very specific usage of "which" :
- for a non essential modifier.
- as an object of a preposition.