In a cross in Drosophila , the heterozygous member with grey body `(b^(+))` and long wings `(vg^(+))` was crossed with had the following ratio grey vestigial 24 : grey long 126: black long 26 : black vestigial 124 . What is the frequency of recombinant in the population ?

Options

A. `15.8%`
B. `16.7%`
C. `17.5%`
D. `14.5%`

Answer

To solve the problem, we need to calculate the frequency of recombinant offspring in a cross of Drosophila with the given phenotypic ratios.

### Step-by-Step Solution:

1. **Identify the Parental and Recombinant Phenotypes**:
- The parental phenotypes are:
- Grey body with long wings (B+ vg+)
- Black body with vestigial wings (bb vg)
- The recombinant phenotypes are:
- Grey body with vestigial wings (B+ vg)
- Black body with long wings (bb vg+)

2. **Count the Offspring**:
- From the given ratios:
- Grey vestigial (recombinant) = 24
- Grey long (parental) = 126
- Black long (recombinant) = 26
- Black vestigial (parental) = 124

3. **Calculate Total Offspring**:
- Total offspring = Grey vestigial + Grey long + Black long + Black vestigial
- Total = 24 + 126 + 26 + 124 = 300

4. **Calculate the Number of Recombinant Offspring**:
- Number of recombinant offspring = Grey vestigial + Black long
- Number of recombinants = 24 + 26 = 50

5. **Calculate Recombination Frequency**:
- Recombination frequency (RF) = (Number of recombinants / Total offspring) × 100
- RF = (50 / 300) × 100 = 16.67%

### Final Answer:
The frequency of recombinant in the population is **16.67%**.