Fish with stout and strong fins could move on land and go back to water. This was about

Options

A. 350 mya
B. 320 mya
C. 500 mya
D. 200 mya

Explanation

**Step-by-Step Solution:**

1. **Identify the Characteristics of the Fish:**
- The question describes fish with stout and strong fins. These characteristics suggest that the fish are adapted for both aquatic and terrestrial environments.

2. **Determine the Time Period:**
- The question provides several options regarding the time period when these fish existed. The options are 350 million years ago (MYA), 320 MYA, 500 MYA, and 200 MYA.

3. **Recall Relevant Evolutionary History:**
- Fish that could move onto land are often associated with the evolutionary transition from water to land. This transition is believed to have occurred during the Devonian period, which is approximately 350 million years ago.

4. **Select the Correct Option:**
- Based on the characteristics of the fish and the time period associated with the transition from aquatic to terrestrial life, the correct answer is 350 million years ago (MYA).

5. **Conclude the Answer:**
- Therefore, the fish with stout and strong fins that could move on land and back to water existed around 350 million years ago.

**Final Answer:**
- The correct answer is 350 million years ago (MYA).

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