Which statement correctly describes the use of probability in genetics?

Which statement correctly describes the use of probability in genetics?

• A. Probability predicts the exact outcomes of every individual cross.
• B. Probability is used to predict the outcomes of genetic crosses.
• C. Probability measures only phenotype frequencies.
• D. Probability is unrelated to inheritance.

Answer: (B)

Probability in genetics is about how likely different genetic outcomes are when alleles segregate and combine in offspring. It lets us predict the expected frequencies of genotypes and phenotypes across many offspring from a cross, not the exact outcome of a single mating. That’s why the statement that probability is used to predict the outcomes of genetic crosses is the best choice. It captures the idea that probabilities describe likelihoods and help us anticipate patterns over many offspring, rather than guaranteeing a particular result for one event. The other ideas are less accurate because a single cross can vary by chance, probability isn’t limited to phenotype frequencies, and probability is a central tool for understanding inheritance.

Probability in genetics is about how likely different genetic outcomes are when alleles segregate and combine in offspring. It lets us predict the expected frequencies of genotypes and phenotypes across many offspring from a cross, not the exact outcome of a single mating. That’s why the statement that probability is used to predict the outcomes of genetic crosses is the best choice. It captures the idea that probabilities describe likelihoods and help us anticipate patterns over many offspring, rather than guaranteeing a particular result for one event. The other ideas are less accurate because a single cross can vary by chance, probability isn’t limited to phenotype frequencies, and probability is a central tool for understanding inheritance.