An organism has a gene ' X '. Its dominant allele expresses character c - 1 while it's recessive allele expresses character c - 2 This dominant allele is completely dominant over the recessive allele . It has another gene ' y ' which in its dominant form doesn't allow any expression of gene ' x ' which of these genotypes of that organism Will produce character c - 1 ?

Options

A. xxyy or XxYy
B. XXYY or xxyy
C. xxYy or XXYy
D. Xxyy or Xxyy

Answer

To solve the question, we need to analyze the genetic information provided about the organism and the effects of the alleles involved.

### Step-by-Step Solution:

1. **Understanding Gene X:**
- Gene X has two alleles: a dominant allele (let's denote it as X) that expresses character C1 and a recessive allele (denote it as x) that expresses character C2.
- The dominant allele (X) completely masks the expression of the recessive allele (x).

2. **Understanding Gene Y:**
- Gene Y also has two alleles: a dominant allele (denote it as Y) that inhibits the expression of gene X, and a recessive allele (denote it as y) that allows expression of gene X.
- If the organism has at least one dominant allele Y (YY or Yy), it will not express either character C1 or C2.

3. **Possible Genotypes:**
- We need to determine which genotypes will produce character C1. The possible combinations of alleles for genes X and Y are:
- **1. XXYY** (homozygous dominant for both genes)
- **2. XXYy** (homozygous dominant for X and heterozygous for Y)
- **3. XxYY** (heterozygous for X and homozygous dominant for Y)
- **4. XxYy** (heterozygous for both genes)
- **5. xxYY** (homozygous recessive for X and homozygous dominant for Y)
- **6. xxYy** (homozygous recessive for X and heterozygous for Y)
- **7. Xxyy** (heterozygous for X and homozygous recessive for Y)
- **8. xxyy** (homozygous recessive for both genes)

4. **Analyzing Genotypes for C1 Expression:**
- For character C1 to be expressed, the organism must have at least one dominant allele X (X or Xx) and must not have a dominant allele Y (Y).
- Therefore, the possible genotypes that can express C1 are:
- **XxYy** (heterozygous for X and heterozygous for Y) - C1 is expressed.
- **XXyy** (homozygous dominant for X and homozygous recessive for Y) - C1 is expressed.
- Any genotype that includes at least one Y (YY or Yy) will inhibit the expression of C1.

5. **Conclusion:**
- The only genotype that will produce character C1 is **Xxyy** or **XXyy** (where Y is recessive). Thus, the organism must have at least one dominant allele X and both alleles of Y must be recessive (yy) to express C1.

### Final Answer:
The genotypes of the organism that will produce character C1 are: **Xxyy or XXyy**.