The presence of recessive trait in a large population is be `16%` the frequency of dominant trait in that population is :-

Options

A. `0.84`
B. `0.42`
C. `0.56`
D. `0.96`

Answer

To solve the problem of finding the frequency of the dominant trait in a population where the recessive trait is present at 16%, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Given Information**:
- The presence of the recessive trait in the population is 16%. This means that 16% of the population expresses the recessive phenotype.

2. **Convert Percentage to Decimal**:
- To work with the Hardy-Weinberg principle, we need to convert the percentage into a decimal.
- 16% as a decimal is 0.16.

3. **Identify the Variables**:
- According to the Hardy-Weinberg principle, we denote:
- \( q \) = frequency of the recessive allele
- \( p \) = frequency of the dominant allele
- The relationship between these frequencies is given by the equation:
\[ p + q = 1 \]

4. **Assign the Value of q**:
- Since we know that the frequency of the recessive phenotype (which corresponds to \( q^2 \)) is 0.16, we can find \( q \):
\[ q = \sqrt{0.16} = 0.4 \]
- However, since we are given the percentage of the recessive phenotype directly, we can directly assign \( q = 0.16 \) for the recessive phenotype.

5. **Calculate p**:
- Now, we can find \( p \) using the equation \( p + q = 1 \):
\[ p = 1 - q \]
\[ p = 1 - 0.16 = 0.84 \]

6. **Conclusion**:
- The frequency of the dominant trait in the population is 0.84, which can also be expressed as 84%.

### Final Answer:
The frequency of the dominant trait in that population is **0.84**.

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