How do we know that the mice picked for the experiment weren't approaching the end of their lifespan already? and 'soon' is very vague, isnt it? if we picked 1000 mice about to die in another 3 months, and 20 Mice (Many) indeed died in 4 months(soon)? do we have a say here? Dying 'sooner' than supposed would mean health didn't improve. Plus the scientists concluded 'that the probiotic microbes in the yogurt help to make the animals leaner and healthier', and this statement is general and should be true, unavoidably, for all sorts of studies. I claim that 'cyanide' capsule kills! and a study show's it doesn't. So The study directly refutes my claim. Isn't it?

A team of researchers from the Massa­chusetts Institute of Technology studied the effects of yogurt on mating. The researchers took a group of 40 male mice and 40 female mice and either fed the animals a high-fat, low-fiber, low-nutrient diet meant to mimic junk food or fed them standard mouse meals. They then supple­mented half of each diet group with vanilla-flavored yogurt.In mating experiments, yogurt-eating males inseminated their partners faster and produced more offspring than control mice. Conversely, females that ate the yogurt diets gave birth to larger litters and weaned those pups with greater success. The researchers concluded that the probiotic microbes in the yogurt help to make the animals leaner and healthier, which indirectly improves sexual machismo.

Which of the following if true, would most weaken the conclusion reached by the researchers?

A.Many of the mice in the control group died soon after the experiment

Everybody misunderstood what a control group is so:

Control group Def : - In a particular study, researchers may divide participants into two groups — an "experimental group" and a "control group." The experimental group is given the experimental treatment under study, while the control group may be given either the standard treatment for the illness or a placebo.

so the control group is what that was not treated with youghurt, so they die they dont die not the concern here. Even if it is "Many of the mice in the experimental group died soon after the experiment" I would not have marked it. What if many mice of other group has also died for some other factors. "That's what autopsy's are for" you don't claim anything without discarding all other factors involved.


B.In another study, probiotic microbes were not found to produce any significant health benefits
What if there is another study concludes that probiotic microbes doesnt hep so than it weaken our conclusion. Also if see, there is a huge leap from Mouse to animal.

B weakens. IMO correct


C.Yogurt is not the only food which contains a high concentration of probiotic microbes : - so what?? right now we are only concerned about yoghurt. Also not half of the mice of one group (control or experimental) is given junk food, health food so other food anyways doesn't matter. Also we are concluding that "Probiotic microbes" helps. other conclusion stand correct in any case.

can you help understand the confusion regarding Control group