Structure of protein insulin was first studied by

Options

A. Sanger
B. Stanley
C. Nicholson
D. Watson.

Answer

To answer the question regarding who first studied the structure of the protein insulin, we can follow these steps:

### Step 1: Identify the options given
The options provided are:
1. Sanger
2. Stanley
3. Nicholson
4. Watson

### Step 2: Analyze the contributions of each scientist
- **Sanger**: Frederick Sanger is known for his work on the structure of proteins, particularly insulin. He was awarded the Nobel Prize in Chemistry for his work on the structure of proteins, including the sequencing of insulin.
- **Stanley**: This likely refers to a scientist who contributed to biochemistry but is not specifically known for insulin.
- **Nicholson**: Known for introducing the fluid mosaic model of cell membranes, not for insulin.
- **Watson**: James Watson is famous for co-discovering the structure of DNA with Francis Crick, not for insulin.

### Step 3: Determine the correct answer
Based on the analysis, the correct answer is **Sanger**, as he was the first to study the structure of insulin.

### Final Answer
The structure of the protein insulin was first studied by **Sanger**.

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