Question

practice it! which of the following describes an experimental investigation? a study conducted which involves testing an observation. the scientist changes multiple things during the test. these are the controlled variables. some kind of data is collected and connected back to the observation. a study conducted which involves a scientist looking at something that is known and comparing it to something else. the scientist collects data about how the items are similar and how they are different. a study conducted which involves testing a hypothesis. the scientist manipulates one thing during the test, which is the test (independent) variable. some kind of data is collected and connected back to the hypothesis. a study conducted which involves making observations of the natural world in the wild. the scientists is an observer only and does not manipulate or change anything.

Explanation:

An experimental investigation tests a hypothesis by manipulating an independent variable and collecting data related to the hypothesis. In an experiment, only one variable should be manipulated at a time for valid results. The first option has multiple - controlled variables (should be controlled, not changed multiple), the second is more of a comparative study, and the fourth is an observational study.

Answer:

C. A study conducted which involves testing a hypothesis. The scientist manipulates one thing during the test, which is the test (independent) variable. Some kind of data is collected and connected back to the hypothesis.