Fill in the following blanks with suitable words:
Dolphins and whales breathe through …………..

Options

A. Blowholes
B. Gills
C. Trachea
D. Lungs

Answer

**Step-by-Step Solution:**

1. **Identify the Organisms**: The question mentions dolphins and whales. Both of these animals are classified as mammals.

2. **Understand Their Breathing Mechanism**: Unlike fish, which breathe through gills, dolphins and whales breathe air. They have lungs, similar to humans.

3. **Locate the Breathing Structure**: Dolphins and whales have a special structure that allows them to breathe air while swimming. This structure is located on the top of their heads.

4. **Name the Structure**: The structure through which dolphins and whales breathe is called a "blow hole." This is essentially a nostril that allows them to inhale and exhale air.

5. **Fill in the Blank**: Based on the above information, the correct word to fill in the blank is "blow holes."

**Final Answer**: Dolphins and whales breathe through **blow holes**.

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