The first life on earth was originated by:

Options

A. Chemical synthesis
B. Spontaneous generation
C. Pre existed life
D. Panspermia

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of the first life on Earth. We need to evaluate the given options: chemical synthesis, spontaneous generation, pre-existing life, and panspermia.

2. **Analyzing the Options**:
- **Chemical Synthesis**: This refers to the process where simple organic compounds are formed from inorganic substances. It is believed that in the primitive Earth environment, conditions were suitable for the formation of organic molecules like amino acids, sugars, and nucleotides, which are the building blocks of life.
- **Spontaneous Generation**: This is the outdated theory that life can arise from non-living matter spontaneously. This idea has been disproven and is not considered a valid explanation for the origin of life.
- **Pre-existing Life**: This implies that life existed before the first life on Earth. However, the question is about the very first life, which cannot come from pre-existing life.
- **Panspermia**: This theory suggests that life exists throughout the universe and is distributed by space dust, meteoroids, comets, etc. While intriguing, it does not explain how life originated on Earth.

3. **Conclusion**: Based on the analysis, the most scientifically accepted explanation for the origin of the first life on Earth is through **chemical synthesis**. This process led to the formation of organic compounds in the early Earth environment, which eventually combined to form simple life forms.

4. **Final Answer**: The first life on Earth was originated by **chemical synthesis**.

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