Step 1: Understanding the Question:
This question tests knowledge of insect classification.
Step 2: Detailed Explanation:
Snow-fleas (springtails) belong to the order Collembola.
They are not true fleas (Siphonaptera).
Siphonaptera (A): True fleas (e.g., cat flea).
Thysanura (B): Silverfish.
Collembola (C): Springtails (snow-fleas).
Thysanoptera (D): Thrips.
Thus, snow-fleas belong to Collembola only.
Step 3: Final Answer:
Thus, snow-fleas belong to Collembola, which corresponds to option (C).
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