In the past, infants who were not breast-fed were fed cows milk. Then

Question

In the past, infants who were not breast-fed were fed cow’s milk. Then doctors began advising that cow’s milk fed to infants should be boiled, as the boiling would sterilize the milk and prevent gastrointestinal infections potentially fatal to infants. Once this advice was widely implemented, there was an alarming increase among infants in the incidence of scurvy, caused by vitamin C deficiency. Breast-fed infants, however, did not contract scurvy.

Which one of the following is most strongly supported by the information above?

(A) Boiled cow’s milk makes less vitamin C available to infants than does the same amount of mother’s milk.

(B) Infants who consume cow’s milk that has not been boiled frequently contract potentially fatal gastrointestinal infections.

(C) Mother’s milk can cause gastrointestinal infections in infants.

(D) When doctors advised that cow’s milk fed to infants should be boiled, they did not know that scurvy was caused by vitamin C deficiency.

(E) When doctors advised that cow’s milk fed to infants should be boiled, most mothers did not breast-feed their infants.

guddo · Answer

In the past, infants who were not breast-fed were fed cow’s milk. Then doctors began advising that cow’s milk fed to infants should be boiled, as the boiling would sterilize the milk and prevent gastrointestinal infections potentially fatal to infants. Once this advice was widely implemented, there was an alarming increase among infants in the incidence of scurvy, caused by vitamin C deficiency. Breast-fed infants, however, did not contract scurvy.
 
 Which one of the following is most strongly supported by the information above?

After cow’s milk began being boiled, scurvy increased among infants who were fed that milk. Scurvy is caused by vitamin C deficiency, while breast-fed infants did not get scurvy.  So the passage supports the idea that boiled cow’s milk provided less available vitamin C than mother’s milk did .

(A) Boiled cow’s milk makes less vitamin C available to infants than does the same amount of mother’s milk.

This is correct. The increase in scurvy after boiling cow’s milk, together with the fact that breast-fed infants did not contract scurvy, supports this comparison.

(B) Infants who consume cow’s milk that has not been boiled frequently contract potentially fatal gastrointestinal infections.

This is not supported. Doctors believed boiling would prevent such infections, but the passage does not tell us how frequently infants drinking unboiled cow’s milk contracted them.

(C) Mother’s milk can cause gastrointestinal infections in infants.

This is not supported. The passage says breast-fed infants did not contract scurvy, but says nothing about mother’s milk causing infections.

(D) When doctors advised that cow’s milk fed to infants should be boiled, they did not know that scurvy was caused by vitamin C deficiency.

This is not supported. The passage does not tell us what doctors knew about scurvy at the time.

(E) When doctors advised that cow’s milk fed to infants should be boiled, most mothers did not breast-feed their infants.

This is not supported. The passage discusses infants who were not breast-fed, but gives no information about whether they were the majority.

Answer: (A)

sidvinod69 · Answer

But, the passage doesn't conclude the fact the at Scurvy is a sign of "not drinking Mother's milk", they can happen to be two random events as well.
Also, B suggests that drinking not-boiled milk can contract intestinal infections, which is mentioned directly in the second sentence. No way to disprove option B in my opinion.

guddo · Answer

A does not say scurvy is simply a sign of “not drinking mother’s milk.” It says boiled cow’s milk made less vitamin C available than mother’s milk. That is supported by the pattern: after cow’s milk was boiled, scurvy increased, and scurvy is caused by vitamin C deficiency, while breast-fed infants did not get scurvy.

This is a “most strongly supported” question, so the answer does not need to be proven with 100 percent certainty. It only needs to be the best-supported inference.

B is too strong. The passage says doctors believed boiling would prevent potentially fatal gastrointestinal infections. But it does not say that infants drinking unboiled cow’s milk  frequently  got those infections. “Potentially fatal” means the infections could be fatal, not that they happened often.

So A is supported by the vitamin C/scurvy contrast, while B adds an unsupported  frequency  claim.

egmat · Answer

Hi sidvinod69,

You're holding this choice to a "can it be disproven?" test, and that's actually the heart of the confusion. This is a  most strongly supported  (inference) question, not a strengthen/weaken one. The job isn't to find a choice you  can't  knock down - it's to find the choice the passage  actively points to . "I can't disprove B" isn't enough; the passage has to give you B.

On your coincidence worry for A

You're right that the passage never  says  scurvy is a sign of "not drinking mother's milk," and on a weaken question your instinct would be sharp. But notice the timing the passage hands us: scurvy spiked  right after  boiling became widespread, and breast-fed infants - who never got the boiled milk - didn't get scurvy. Boiling is the one thing that changed. Since scurvy is a vitamin C deficiency, the cleanest read of those two facts together is that boiled cow's milk delivered  less available vitamin C  than mother's milk. That's not a wild leap - it's the explanation the passage's own facts are leaning on. That's A.

On B - this is the key fix

The passage says boiling  would prevent  gastrointestinal infections. Watch the direction. "Boiling prevents infections" tells you what the  boiled  milk does - it does  not  tell you that  unboiled  milk  frequently  causes  potentially fatal  infections. That's the doctors' stated worry, not a reported rate. B smuggles in two things the text never gives: how  often  it happens ("frequently") and that it's actually fatal in practice.

Quick test - flip one word. If B had said "doctors  believed  unboiled milk could cause infections," it'd be supported. As written, with "frequently contract," it overstates what the passage licenses.

Answer: A

In the past, infants who were not breast-fed were fed cows milk. Then

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