How would the human population be different if crossing over did not happen during meiosis

Ascientist conducted an investigation about the effects of diet on disease resistance in rats and made surprising observations. the mice with a genetic ear mutation seemed to show similar patterns of resistance compared to mice with normal ears. based on this information, what will most likely occur? a.she will perform a second investigation on the role of certain genes in disease resistance. b.she will revise her hypothesis to pertain to mutations rather than diet, and update her data accordingly. c.she will use this information to determine that her original question was nonscientific, so she will revise it. d.she will determine that her hypothesis was invalid because resistance must be genetic.