Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
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Question: Ultrasound, a diagnostic technology, uses high-frequency vibrations transmitted into any tissue in contact with the transducer.

Answer: What diagnostic technology uses high-frequency vibrations transmitted into any tissue in contact with the transducer?

Question: Herbivores is the term for animals that eat producers to get energy.

Answer: What is the term for animals that eat producers to get energy?

Question: The ice crystals that form on the ground are called frost.

Answer:
What are the ice crystals that form on the ground called?