What is a hypothesis?

A hypothesis is indeed a testable statement about variables. In scientific research, a hypothesis provides a specific prediction that can be investigated through experimentation or observation. It usually expresses a relationship between two or more variables, allowing researchers to design experiments to confirm or refute the hypothesis based on the collected data.

For example, if a scientist proposes that increasing the amount of sunlight a plant receives will result in taller plant growth, this suggests a direct relationship between sunlight (independent variable) and plant height (dependent variable). This hypothesis can be tested with controlled experiments, making it a fundamental part of the scientific method.

The other mentioned choices do not accurately capture the nature of a hypothesis. A hypothesis is not a proven fact; rather, it is a starting point for investigation. It also isn’t an untestable idea; if it cannot be tested, it does not fulfill the criteria for a hypothesis. Lastly, a hypothesis differs from a scientific theory, which is a broader explanation of phenomena supported by a large body of evidence and well-established through multiple hypotheses and experiments.