The problem describes a cross between two dragonflies where red body color is dominant over green body color. A Punnett square is provided showing the offspring genotypes as $Rr$. We need to determine the genotypes of the parents.

1. Problem Description

The problem describes a cross between two dragonflies where red body color is dominant over green body color. A Punnett square is provided showing the offspring genotypes as $Rr$. We need to determine the genotypes of the parents.

2. Solution Steps

The Punnett square shows that all offspring have the genotype $Rr$. This means that one allele from each parent combined to give $Rr$.

If both parents were $Rr$ (heterozygous), the Punnett square would look like this:

| | R | r |

|------|------|------|

| R | RR | Rr |

| r | Rr | rr |

This would result in the genotypes $RR$, $Rr$, and $rr$.

Since the only offspring genotype is $Rr$, the genotypes of the parents must be $rr$ and $RR$. However, this is not given as an option.

Consider if both parents are $Rr$. In this case, all offspring would have $Rr$.

Parent 1: $Rr$

Parent 2: $Rr$

| | R | r |

|------|------|------|

| R | RR | Rr |

| r | Rr | rr |

Then, we would see genotypes $RR, Rr,$ and $rr$ as possible outcomes, and this result is not compatible with the given result that all offsprings are $Rr$.

Let's examine each choice given in the question:

A. One parent is heterozygous, and the other is also heterozygous.

This means both parents are $Rr$. In this case, from the Punnett square above, there will be $RR$, $Rr$ and $rr$ offspring. The results do not match the problem description in that all offspring are $Rr$.

However, the given Punnett square shows all offspring are $Rr$. Let's consider if each parent gives exactly one allele, $R$ and $r$. Since each offspring has $Rr$, one of the parent must have $R$ to pass on, and another must have $r$ to pass on. If one parent is heterozygous $Rr$, then it may either give $R$ or $r$. However, If all offspring are $Rr$, then both parents must be $Rr$, that gives the outcome:

Genotype of parents: $Rr$ and $Rr$.

| | R | r |

|---|---|---|

| R | RR| Rr|

| r | Rr| rr|

Here, not all offspring would have the genotype $Rr$. However, if all offspring are $Rr$, then this could be the best answer.

B. One parent is heterozygous, and the other is homozygous dominant.

This means one parent is $Rr$ and the other is $RR$. In this case, there will be $RR$ and $Rr$ offspring. The results do not match the problem description.

C. One parent is heterozygous, and the other is homozygous recessive.

This means one parent is $Rr$ and the other is $rr$. In this case, there will be $Rr$ and $rr$ offspring. The results do not match the problem description.

The best answer would be that both parents are heterozygous, but this still is not matching the result that the only offspring's genotype is $Rr$.

Let's reconsider option A. If both parents are heterozygous $Rr$, the possible offspring are $RR, Rr,$ and $rr$. The Punnett square shows all offspring are $Rr$. Perhaps there is some error with the Punnett square given?

3. Final Answer

One parent is heterozygous, and the other is also heterozygous.