If a tall stem is a dominant characteristic, in which case is the characteristic of tall definitely expressed? a. when both alleles contain instructions for tall b. when at least one allele contains instructions for tall c. when at least one parent is tall d. when both parents are tall the answer is not a

Hi there!

The phenotype for a dominant allele will show up whenever the dominant allele is present. Due to it being dominant, it overrides all other phenotypes for that trait. Therefore, the answer is B - When at least one allele contains instructions for tall.

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