instruction:
Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.
question:
Fact: high temperatures can cause an object to combust
answer:
A dry bush may burst into flames due to?


question:
Fact: earthworms create tunnels in soil
answer:
Moles are underground a lot of the time, and since few animals live there, they are unlikely to be?


question:
Fact: sugar causes food to taste sweet
answer:

What stimulants taste buds sour and?