The correct answer is A) 9/16.
To determine the proportion of peas that would be green and smooth in the dihybrid cross, we need to understand the principles of Mendelian genetics and Punnett squares.
In a dihybrid cross, we consider two traits that are controlled by different genes and segregate independently. Let's assume that the two traits in this case are color (green or yellow) and texture (smooth or wrinkled).
A Punnett square is a helpful tool for predicting the possible combinations of alleles from the parents. In this case, the parents are both heterozygous for both traits, meaning they carry one dominant and one recessive allele for each trait.
So, the Punnett square would look like this:
| Gg | Gg |
--------------------------
Ss | GgSs | GgSs |
--------------------------
Ss | GgSs | GgSs |
The combinations in the Punnett square represent the possible genotypes of the offspring. To determine the phenotypes (observable traits), we need to consider the dominant and recessive alleles for each trait.
In this case, green (G) is dominant over yellow (g), and smooth (S) is dominant over wrinkled (s).
Looking at the Punnett square, we see that there are 9 combinations that have the genotype GgSs, which corresponds to green and smooth peas.
Since there are a total of 16 possible combinations (4 boxes in the Punnett square multiplied by 4 boxes), the proportion of peas that would be green and smooth is 9/16.