B. It must be testable.
A scientific question must be testable because science relies on empirical evidence. This means that questions must be framed in a way that allows them to be investigated through experiments or observations. The ability to test a question allows scientists to gather data and draw conclusions based on evidence, which is fundamental to the scientific method.
The other options:
A. It must be ethical - While ethical considerations are important in scientific research, this is not a requirement for a scientific question itself. Ethical standards come into play in how the research is conducted and how data are collected.
C. It must question existing ideas - While many scientific questions do indeed challenge existing ideas, it's not a requirement for a question to be scientific. Scientific questions can also explore unknown phenomena or seek to understand how something works without directly challenging existing ideas.
D. It must be proved correct - Science doesn't seek to prove things "correct" but rather to develop explanations that are supported by evidence. Scientific theories are continually tested and refined, and they are considered valid as long as they continue to be supported by evidence.
