2. According to the passage, which of the following is true of the experiments on domestic hens conducted by Sherwin's research team?

(A) Only a small number of observer hens appeared to learn to avoid food that was demonstrated by other hens to be noxious.

Not true. There was no evidence.
"Even when demonstrator hens reacted with obvious disgust to a specific food, via vigorous head shaking and bill wiping, there was no evidence that observers subsequently avoided eating that food."

(B) Observer hens ingested food preferentially only after numerous instances of witnessing demonstrator hens preferentially ingest that type of food.

Not true. Not given that numerous instances were needed.
"if observer hens watched demonstrator hens react favorably to food of a particular color, then observer hens ate more food of that color than they ate of food of other colors."

(C) Observer hens appeared unable to recognize when demonstrator hens found a particular food especially palatable.

Not true.
"if observer hens watched demonstrator hens react favorably to food of a particular color, then observer hens ate more food of that color than they ate of food of other colors."

(D) Demonstrator hens reacted adversely to ingesting certain novel foods.

True. They were fed some novel foods that were noxious or toxic and they reacted adversely.

"Sherwin's recent experiments with domestic hens do not support the notion that avian social learning necessarily facilitates aversion to novel foods that are noxious or toxic. Even when demonstrator hens reacted with obvious disgust to a specific food, via vigorous head shaking and bill wiping, there was no evidence that observers subsequently avoided eating that food."

(E) Demonstrator hens altered their behavior less obviously in response to noxious foods than in response to highly palatable foods.

Not true. Not given whether demonstrator hens' behaviour was more or less vigorous in the two cases. We only know that the observer hens reacted differently.

Answer (D)
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The problem is that the passage distinguishes between demonstrator and observer hens. We know that observers did not necessarily avoid eating the noxious foods, and the observers reacted favorably to palatable foods. But (E) speaks about the DEMONSTRATORS. We don’t know how much the DEMONSTRATOR hens altered their behavior in response to noxious or palatable foods, so we can eliminate (E).

I hope that helps!
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