The question asks us to choose the answer option which would not negate the findings of the study reported in the passage.

Consider option 1. If the penguins’ plumage were made of a material that did not allow any heat transfer through convection or radiation, then the birds cannot minimize heat loss using their plumage. This negates the findings of the study.

Let us look at option 2. If the average air temperature recorded during the month of June 2008 in the area of study were –10 degrees Fahrenheit (instead of 0.32 degrees Fahrenheit reported in the study) and the penguins’ plumage on their heads, chests and backs were at -1.84, -7.24 and -9.76 degrees Fahrenheit, then the birds’ plumage would be warmer than the surrounding air, making heat gain due to convection impossible. So, option 2 too goes against the findings of the study.

Consider option 3. If the temperature of the plumage on the penguins’ heads, chests and backs were found to be 1.84, 7.24 and 9.76 degrees Fahrenheit respectively, then the plumage would be much warmer than the surrounding air. This would mean heat loss for the penguins. Option 3, too, negates the findings of the study.

Let us look at option 4. If the average temperature of the feet of penguins in the month of June 2008 were found to be 2.76 degrees Fahrenheit, instead of 1.76 degrees Fahrenheit, the findings of the study would still hold good. This is the option that does not negate the findings of the study.