If a Punnett square has 3 dominant traits and 1 recessive trait, what would the ratio be?

In this scenario, you are examining the offspring probabilities resulting from a genetic cross involving one dominant trait and one recessive trait for a single gene. When both parents are heterozygous for a trait (which means they have one dominant and one recessive allele), a Punnett square can be used to visualize the potential trait combinations in the offspring.

If there are three dominant traits and one recessive trait specifically related to the setup of the square, it suggests a situation where all offspring will express the dominant phenotypes. In a typical Punnett square for a single trait, the classic ratio of phenotypes for two heterozygous parents (when considering one dominant and one recessive trait) results in a 3:1 ratio, meaning three offspring would express the dominant trait for every one that shows the recessive trait.

Thus, when you have 3 dominant traits with 1 recessive trait and only those traits to account for, the offspring ratio is expressed without consideration for the recessive allele in the phenotype. Hence, if both parents contribute dominant traits, all offspring will express the dominant traits in the simplest interpretation, leading to a ratio of 4:0 for dominant traits.

The option suggesting 2:2:0