Franklin and Wilkins showed that DNA

Options

A. Contains four bases
B. Is a helix
C. Has equal amount of adenine and thymine
D. Is made up of nucleotides

Explanation

**Step-by-Step Solution:**

1. **Understanding the Contribution of Franklin and Wilkins:**
- Rosalind Franklin and Maurice Wilkins were key figures in the discovery of the structure of DNA. They used X-ray diffraction techniques to study DNA.

2. **Key Findings:**
- **Helical Structure:** They demonstrated that DNA has a helical structure. This was evident from the X-ray diffraction patterns they obtained, which suggested that DNA is twisted in a spiral shape.
- **Base Composition:** They also contributed to the understanding that DNA contains four nitrogenous bases: adenine (A), thymine (T), cytosine (C), and guanine (G).
- **Base Pairing:** Although Franklin and Wilkins did not explicitly state the base pairing rules, their work laid the groundwork for later discoveries that adenine pairs with thymine and cytosine pairs with guanine.

3. **Nucleotide Composition:**
- DNA is made up of nucleotides, which are the building blocks of DNA. Each nucleotide consists of a sugar (deoxyribose), a phosphate group, and a nitrogenous base.

4. **Conclusion:**
- Franklin and Wilkins' research significantly advanced the understanding of DNA's structure and composition, leading to the eventual elucidation of the double helix model by Watson and Crick.

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