To determine the correct sequence of events in the origin of life, we will analyze the provided statements step by step.
### Step 1: Identify the First Event
The first event in the origin of life is the **synthesis of organic monomers**. These are the basic building blocks of life, such as amino acids, nucleotides, and simple sugars, which are essential for forming more complex molecules.
**Hint:** Think about the simplest components necessary for life; they must come first.
### Step 2: Identify the Second Event
The second event is the **synthesis of organic polymers**. Once the organic monomers are available, they can chemically bond together to form larger molecules known as polymers. For example, amino acids can link to form proteins, and nucleotides can link to form nucleic acids.
**Hint:** Consider what happens when monomers combine; they create larger structures.
### Step 3: Identify the Third Event
The third event is the **formation of protobionts**. Protobionts are primitive structures that can maintain an internal environment and are considered precursors to living cells. They are formed from the aggregation of organic polymers and can exhibit some characteristics of life, such as metabolism and reproduction.
**Hint:** Think about how these larger structures could start to behave like living entities.
### Step 4: Identify the Fourth Event
The final event is the **formation of DNA-based genetic systems**. Over time, protobionts evolved to include more complex structures, leading to the development of genetic material, specifically DNA, which is crucial for heredity and the functioning of living organisms.
**Hint:** Reflect on the importance of genetic material in the continuity of life.
### Conclusion
Putting all these steps together, the correct sequence of events in the origin of life is:
1. Synthesis of organic monomers (II)
2. Synthesis of organic polymers (I)
3. Formation of protobionts (III)
4. Formation of DNA-based genetic systems (IV)
Thus, the correct order is II, I, III, IV.
### Final Answer
The correct sequence is: **II, I, III, IV** (Option 3).
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