Tough and confused parallelism - need the help of expert

[tuanquang269]

I searched this question on google and did not find nothing for the explanation of this question.

The human growth hormone, made by the pituitary gland, is secreted during sleep in higher concentrations than when awake.
(A) during sleep in higher concentrations than when awake
(B) when sleeping in higher concentrations than waking hours
(C) in higher concentrations during sleeping than waking
(D) in higher concentrations during sleep than during waking hours
(E) in higher concentrations when asleep than when awake

OA is D

IMO E

[hoji]

some thoughts related to the use of "during"

(BTG)rule: [during+particular time period]

-during two hours, i felt sleepy - incorrect;
-during the past two hours, i felt sleepy - correct.
if we take this rule as granted, then the options in which "during" is used are incorrect! because they don't talk about particular time period, rather they talk about time period in general.

Experts, please shed some light on this!

[karthikgmat]

confused between D and E

[satishchandra]

A,B,C violate parallelism. I think we all eliminated those 3 choices in one go.

Now, Between D and E

I think both are not looking good

D) during sleeping hours than during waking hours is correct parallelsm. But do we ever say waking hours?

E) does not seem to be good either

when one is asleep than when one is awake makes correct sense.

What's the source of this question?

[imskpwr]

I think both D & E are incorrect as there is ambiguity.

In D Comparison is made bw
High concentration during Sleeping Hour.
High concentration during Waking Hour.(doesn't look correct as meaning changed)

Similar construction is used in E.

[shankar.ashwin]

'When' and 'Where' should always refer to a time period and place respectively.

E uses 'When' but does not have any time period associated to it.

'Asleep' is not a time period while 'During sleep' is.

[aspirant2011]

I think E changes the intended meaning......

[Jim@Grockit]

Choice E has the growth hormone asleep and awake, which is contrary to modern science.

[GmatVerbal]

I have seen couple of OG questions testing difference between during and when;

my observation is 'when' normally starts a subordinate clause,but if it starts a phrase, care must be taken as 'when ' gets attached to subject of the main clause;

asleep and awake are adjectives they get attached to subject 'human growth hormone';

during is a preposition with noun objects sleep and walking hours;

[Stuart@KaplanGMAT]

Hi,

none of the answers are very good; it's very helpful for the BTG community to know the source of all of your questions (so you should always include the source when you make a new post) - where does this one come from?

[rajeevrks27]

d seems to be the best out of worst I believe

[tuanquang269]

Sorry all guy, my internet cable has problem in recent day. I confronted this question from SC1000.

Besides, can any one help me to summarize the use of when/during in all cases?