Klinefelter's syndrome has

Options

A. 44 + XXY
B. 44 + XO
C. 45 + XY
D. 66 + XXY

Answer

To solve the question regarding Klinefelter's syndrome, we need to understand the genetic basis of this condition. Here’s a step-by-step solution:

### Step 1: Understand Klinefelter's Syndrome
Klinefelter's syndrome is a genetic disorder that occurs in males due to the presence of an extra X chromosome.

**Hint:** Remember that Klinefelter's syndrome is specifically associated with males and involves an additional X chromosome.

### Step 2: Determine the Karyotype
The typical karyotype for males is 46 chromosomes, which includes one X and one Y chromosome (XY). In Klinefelter's syndrome, there is an additional X chromosome, resulting in a total of 47 chromosomes.

**Hint:** Karyotypes are represented by the number of chromosomes and their types. Pay attention to the total number of chromosomes and the sex chromosomes.

### Step 3: Analyze the Options
Now, let's analyze the options provided:
- A) 44 + XXY
- B) 44 + X0
- C) 45 + XY
- D) 66 + XXY

From our understanding, Klinefelter's syndrome is characterized by the karyotype 47, which corresponds to 44 autosomes and 3 sex chromosomes (XXY).

**Hint:** Look for the option that adds up to 47 chromosomes with the correct sex chromosome composition.

### Step 4: Identify the Correct Answer
The correct karyotype for Klinefelter's syndrome is 44 + XXY, which corresponds to option A.

**Hint:** Always double-check your calculations and ensure that the karyotype matches the description of the syndrome.

### Final Answer
The answer is **A) 44 + XXY**.