Give scientific reasons.
Fish has a streamlined body.

Explanation

**Step-by-Step Solution:**

1. **Definition of Streamlined Body**: A streamlined body is one that is shaped to reduce resistance when moving through a fluid, such as water. In fish, this means that the body is narrow at both the front (mouth) and back (tail) and broad in the middle.

2. **Reduction of Drag**: The streamlined shape of a fish helps to reduce drag, which is the resistance force that opposes the motion of the fish through water. When a fish swims, it pushes against the water, and a streamlined body allows it to move more efficiently.

3. **Reduction of Friction**: The design of a streamlined body also minimizes friction between the fish and the water. Lower friction means that the fish can swim with less effort, conserving energy while moving.

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