Provide your best answer for the following question. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The question is: Gregor Mendel studied ratios related to traits passed from parent pea plants to offspring pea plants. Mendel used large numbers of plants to avoid "sampling error." This changed the way scientists studied genetics because it included ideas of
mathematics and probability.
dominant and recessive traits.