Mendel investigates stem length, or height in pea plants what if he had investigated human height instead why would his results have been harder to interpret

Human height is one of the traits that belong to traits that cannot easily be placed in discrete phenotypic classes (there is not only tall and short people, there is continuous variation of height between them). Such traits are usually controlled by more than one gene (polygenic traits).

On the other hand, a Mendelian trait is controlled by a single locus.

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c is the correct answer!