Hydrocarbons were first isolated from plant latex by

Options

A. Krebs
B. Calvin
C. Walksman `
D. Crystal et al

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who first isolated hydrocarbons from plant latex. Hydrocarbons are organic compounds consisting entirely of hydrogen and carbon, and they can be derived from various natural sources, including plant latex.

2. **Identifying Relevant Plant Families**: The family of plants known for producing latex and hydrocarbons is the Euphorbiaceae family. This family includes many species that are capable of producing significant amounts of latex, which contains hydrocarbons.

3. **Recognizing Key Scientists**: The scientist who is most notably associated with the study of hydrocarbons from the Euphorbiaceae family is Melvin Calvin. He conducted research that contributed to our understanding of the photosynthetic process and the production of hydrocarbons in these plants.

4. **Eliminating Other Options**: The other options provided in the question (Krebs cycle, Walksman, Crystallator) do not relate to the isolation of hydrocarbons from plant latex. The Krebs cycle is a metabolic pathway, Walksman is not a relevant figure in this context, and Crystallator does not pertain to this subject.

5. **Conclusion**: Based on the information gathered, the correct answer to the question is Melvin Calvin, who first isolated hydrocarbons from plant latex.

**Final Answer**: Hydrocarbons were first isolated from plant latex by Melvin Calvin.

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