NEET BIOLOGY

Detailed explanation-1: -When the use of experiments to answer questions is impossible or unethical, scientists test predictions by examining correlations.

Detailed explanation-2: -Sometimes, it is not possible to do a controlled experiment. In such cases, scientists depend on observation to test their hypotheses. By observing nature, scientists can collect large amounts of data. If the data support a hypothesis, the hypothesis is probably correct.

Detailed explanation-3: -Natural experiments are often used to study situations in which controlled experimentation is not possible, such as when an exposure of interest cannot be practically or ethically assigned to research subjects.

Detailed explanation-4: -How are hypotheses tested? When possible, scientists test their hypotheses using controlled experiments. A controlled experiment is a scientific test done under controlled conditions, meaning that just one (or a few) factors are changed at a time, while all others are kept constant.