Let's analyze the given Punnett square to determine the phenotype ratio for the cross between two cats. We'll start by identifying the genotypes that result from this cross:
[tex]\[
\begin{array}{|c|c|c|}
\hline & S & s \\
\hline
S & S S & S s \\
\hline
s & S s & s s \\
\hline
\end{array}
\][/tex]
Each cell in the Punnett square represents a possible genotype for the offspring. We need to count each genotype:
1. SS: This genotype comes from the top left cell.
2. Ss: This genotype comes from the top right and bottom left cells, so we have two instances of Ss.
3. ss: This genotype comes from the bottom right cell.
Next, we need to determine the phenotype for each genotype:
- SS: This results in short whiskers because at least one dominant allele (S) is present.
- Ss: This also results in short whiskers since one dominant allele (S) is sufficient to express the short whisker trait.
- ss: This results in long whiskers because there are no dominant alleles (S) present.
Now, we count the number of each phenotype:
- Short whiskers (SS or Ss): 1 (SS) + 2 (Ss) = 3
- Long whiskers (ss): 1
Therefore, the phenotype ratio for this cross is:
[tex]\[
\text{Short whiskers : Long whiskers} = 3 : 1
\][/tex]
Thus, the correct answer is:
C. 3 short, 1 long
