Who among these contributed to the double-helical model of DNA?

Options

A. Wilkins
B. Crick
C. Watson
D. All of them

Explanation

To solve the question of who contributed to the double-helical model of DNA, we can follow these steps:

### Step 1: Identify the Scientists
We need to identify the scientists mentioned in the options provided in the question. The options are:
1. Wilkins
2. Creek (Francis Crick)
3. Watson (James Watson)
4. All of them

### Step 2: Understand Their Contributions
Next, we should understand the contributions of each scientist:
- **James Watson and Francis Crick**: In 1953, they proposed the double-helical model of DNA based on their research and analysis.
- **Maurice Wilkins**: He contributed by providing critical X-ray diffraction data that helped Watson and Crick in their model.
- **Rosalind Franklin**: Although not mentioned in the options, she was also crucial in obtaining the X-ray diffraction images that were pivotal for understanding DNA's structure.

### Step 3: Analyze the Options
Now, we analyze the options:
- Option 1 (Wilkins): He contributed but was not the sole contributor.
- Option 2 (Creek): This is a reference to Francis Crick, who was one of the main contributors.
- Option 3 (Watson): He is also a main contributor.
- Option 4 (All of them): This option includes all the significant contributors, including Wilkins and Crick.

### Step 4: Conclusion
Since all the mentioned scientists (Watson, Crick, and Wilkins) played a role in the development of the double-helical model of DNA, the correct answer is:
**D. All of them.**