CR: The human body secretes more pain-blocking hormones

[direstraits007]

The human body secretes more pain-blocking hormones late at night than during the day. Consequently, surgical patients operated on at night need less anesthesia. Since larger amounts of anesthesia pose greater risks for patients, the risks of surgery could be reduced if operations routinely took place at night.
Which of the following, if true, argues most strongly against the view that surgical risks could be reduced by scheduling operations at night?

(A) Energy costs in hospitals are greatly lower at night than they are during the day.

(B) More babies are born between midnight and seven o’clock in the morning than at any other time.

(C) Over the course of a year, people’s biological rhythms shift slightly in response to changes in the amounts of daylight to which the people are exposed.

(D) Nurses and medical technicians are generally paid more per hour when they work during the night than when they work during the day.

(E) Manual dexterity and mental alertness are lower in the late night than they are during the day, even in people accustomed to working at night.

OA: E.

I got this question in one of the ETS Paper Tests.

My answer on this is C because if the bilogical rhtythms will shift then after some time may be human body secrete more pain-blocking hormones at day than during the night. So in that case the surgical methods cant be performed at night and more risk could be there at day.
please correct me if I'm wrong.

Also E says "Manual dexterity and mental alertness are lower in the late night" which means that surgical operation's pain will not be felt much to the patients at night and can be carried easily at night. So in this case we are actually supporting the argument rather than going against it.

Thanks

[raja.asu]

Choice C is true only when patients stay in hospitals for years and their exposur to daylight is affected. That too slightly. And also, it says biological rythms which has nothing to do with the secretion od pain-blocking harmones.

Choice E: is CORRECT. If manual dexterity and mental alertness are lower in late night, doctors performing surgical operations won't do their best job.Hence, risk of surgery cacnnot be reduced during night time.

[JonathanSchneider]

Raja has it correct here. The key is to notice that there is a difference between doctors and patients.

Patients underdoing surgery late at night will NOT have to adjust for a very long time to being awake at night. They can simply come in for the surgery.

Doctors and nurses, however, WILL have to adjust to night-time work. E states that even once they have adjusted, they will still have less dexterity/alertness than they would during the day. This strongly argues against the benefits to patients of night-time surgery.