What do use scientists use to support a scientific explanation?

Science means "to know" and scientists actively seek to explain natural phenomena using observations, inductive reasoning and logic.

A logical way to find out the answer to a question or problem is by using the scientific method of problem solving.

First, a scientist poses a well-constructed question about something he or she would like to learn the answer to.

Next, a scientist will conduct research on what is already known about this topic. Using observations and prior knowledge, the scientist will try to formulate an answer to the question or problem which is known as a hypothesis. It is an explanation that needs to be supported by evidence.

A good hypothesis is one that can be tested by a controlled experiment. The information gathered during an experiment is known as data. Data can be qualitative, which uses descriptive terms like "on day 2, the plant grew" or quantitative which involves careful measurements--the length of the plant on day 2 was 6.2 cm. 

It is data that can support or refute a hypothesis or scientific explanation. If the data supports the hypothesis, the experiment should be repeated many times with large numbers of subjects to increase the chances that the results are valid. If the data doesn't support the explanation which happens often in science, it is a learning experience and a chance for the scientist to formulate a new hypothesis to be tested.