I'll give you a question, please answer with step-by-step reasoning process.
Pick which sentence is not logical.\nOptions:\n- Sentence A: "Dolphin is a land mammal which is very intelligent and often friendly towards humans."\n- Sentence B: "Dolphin is a sea mammal which is very intelligent and often friendly towards humans."\n

Sentence A
Dolphin swims in the sea; it doesn't have limbs to walk on land.

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Therefore, the answer is Sentence A