Watson, Crick and Wilkins are credited for the discovery that DNA:

Options

A. is a double stranded helix
B. is responsible for the synthesis of tRNA
C. is a carrier of genetic information
D. provides proof for the X-Y chromosomal theory of sex determination

Explanation

To answer the question regarding the contributions of Watson, Crick, and Wilkins to the discovery of DNA, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Key Contributors**: Recognize that James Watson, Francis Crick, and Maurice Wilkins are the scientists credited with significant discoveries related to DNA.

2. **Understand the Structure of DNA**: Watson and Crick proposed that DNA has a double helical structure. This means that DNA is composed of two strands that twist around each other, resembling a spiral staircase.

3. **Recognize the Function of DNA**: DNA serves as the carrier of genetic information. It contains the instructions necessary for the growth, development, functioning, and reproduction of all living organisms.

4. **Eliminate Incorrect Options**: The other options provided in the question (such as being responsible for the synthesis of RNA or providing proof for the X-Y chromosomal theory of sex determination) do not directly pertain to the primary discovery made by Watson, Crick, and Wilkins.

5. **Conclude with the Correct Answer**: Based on the understanding of their contributions, the correct answer to the question is that Watson, Crick, and Wilkins are credited for the discovery that DNA is a double-stranded helix.

### Final Answer:
Watson, Crick, and Wilkins are credited for the discovery that DNA is a double-stranded helix.

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