The double helix model for DNA was proposed by ................ and ............... .

Explanation

To answer the question, "The double helix model for DNA was proposed by ................ and ...............", we can follow these steps:

1. **Identify the Key Concept**: The question is asking for the names of the scientists who proposed the double helix model of DNA.

2. **Recall Historical Context**: The double helix structure of DNA is a significant discovery in molecular biology. It is essential to remember the key figures associated with this discovery.

3. **Name the Scientists**: The scientists who proposed the double helix model of DNA are James Watson and Francis Crick.

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