Which statement identifies a characteristic of a scientific theory?

It is subjective.

It is a proven fact.

It is based on opinion.

It may change over time.

It may change over time.

Explanation:

Scientific theories are not unquestionable truth. That doesn't mean they are just opinions, scientists must provide evidence (laboratory tests, for example) that justify the validity of their conclusion. On the other hand, a theoretical background must be also provided, and this has to be in agreement with other theories already accepted.

It may change over time.

Scientific theory changes with new information. This is famously seen as to how they can't decide if Pluto is a planet or not.