GMAT Critical Reasoning (CR) | Re: Several well known scientists have hypothesized that the food additive

Several well known scientists have hypothesized that the food additive monosodium glutamate – commonly known as MSG – has a negative effect on cognitive function by interfering with important neurotransmitters. A recent experiment was conducted to confirm this hypothesis: over a month period, an experimental group consumed large quantities of MSG, and a similarly sized control group did not consume any MSG. At the end of the period, the experimental group