What is the convergent similarity of a crocodile, a frog and a hippopotamus?

All of these animals spend most of their lives in water. Being in the water, they expose the eyes and nostrils located on the top of the head above its surface, while being able to better navigate and breathe oxygen in the air.
1) These animals have a similar habitat, to which the same adaptations arose.
2) A similar arrangement of the eyes and nostrils on the head (on a hill), which is an adaptation to better vision and breathing.
3) Streamlined body shape.
Answer: A similar arrangement of eyes and nostrils on the head.

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