A marriage between a colourblind man and a normal woman produces

Options

A. all carrier daughters and normal sons
B. `50 %` carrier dauthters, `50 %` normal daughters
C. `50 %` colourblined sons, `50 %` normal sons
D. all carrier offsprings

Explanation

To solve the problem of a marriage between a colorblind man and a normal woman, we need to understand the genetics behind color blindness and how to determine the potential offspring's genotypes. Here’s a step-by-step breakdown:

### Step 1: Understand the Genetics of Color Blindness
Color blindness is a sex-linked recessive trait, which means it is carried on the X chromosome. A colorblind male has the genotype XcY, where Xc represents the X chromosome with the color blindness allele. A normal female has the genotype XX, where both X chromosomes carry the normal vision allele.

**Hint:** Remember that color blindness is a recessive trait linked to the X chromosome.

### Step 2: Determine the Genotypes of the Parents
- The colorblind man has the genotype: XcY
- The normal woman has the genotype: XX

**Hint:** Identify the genotypes of both parents based on their traits.

### Step 3: Determine the Possible Gametes
The male can produce two types of gametes:
- From XcY: Xc and Y

The female can produce two types of gametes:
- From XX: X and X

**Hint:** List the gametes produced by each parent.

### Step 4: Perform a Punnett Square
Now, we can set up a Punnett square to determine the possible genotypes of the offspring:

```
X X
----------------
Xc | XcX | XcX |
----------------
Y | XY | XY |
```

### Step 5: Analyze the Offspring Genotypes
From the Punnett square, we can see the possible offspring:
- Daughters: XcX (carrier daughters)
- Sons: XY (normal sons)

**Hint:** Analyze the results from the Punnett square to determine the genotypes of the offspring.

### Step 6: Determine the Proportions of Offspring
From the analysis:
- All daughters (100%) are carriers (XcX).
- All sons (100%) are normal (XY).

**Hint:** Calculate the percentage of each type of offspring based on the Punnett square results.

### Conclusion
The marriage between a colorblind man and a normal woman produces:
- All carrier daughters (100% XcX).
- All normal sons (100% XY).

Therefore, the correct answer is that all daughters are carriers and all sons are normal.

**Final Answer:** All carrier daughters and normal sons.