How would you produce four O'clock seeds, all of which should yield pink coloured flowers when sown?

Options

A. `RRxxrr`
B. `Rrxxrr`
C. `RrxxRr`
D. `RRxxRr`

Explanation

To produce four o'clock seeds that all yield pink-colored flowers when sown, we need to understand the genetic basis of flower color in four o'clock plants (Mirabilis jalapa). The flower color in these plants exhibits incomplete dominance, where the alleles for flower color interact in a way that results in a blend of traits.

### Step-by-Step Solution:

1. **Identify the Alleles**: In four o'clock plants, the flower color is determined by two alleles:
- R (dominant allele for red flowers)
- r (recessive allele for white flowers)

2. **Understand Incomplete Dominance**: When a plant has one dominant allele (R) and one recessive allele (r), the resulting phenotype is pink flowers. This is because neither allele completely masks the other, leading to an intermediate phenotype.

3. **Determine the Required Genotype**: To ensure that all offspring produce pink flowers, we need to cross plants that will yield only the heterozygous genotype (Rr).

4. **Select the Parent Plants**:
- One parent should be homozygous dominant (RR) for red flowers.
- The other parent should be homozygous recessive (rr) for white flowers.

5. **Perform the Cross**:
- Cross the homozygous red parent (RR) with the homozygous white parent (rr).
- The resulting offspring will all be heterozygous (Rr), which means they will all exhibit the pink flower phenotype.

6. **Sow the Seeds**: After obtaining the seeds from the cross (all Rr), sow these seeds. Since all the seeds are Rr, they will all yield pink flowers when grown.

### Summary of the Cross:
- **Parents**: RR (red) x rr (white)
- **Offspring**: All Rr (pink)