A group of data that will give predictable positive results in an experiment is known as what?

A positive control is a crucial component in experimental design that serves to validate the experimental procedure. It consists of a group or sample that is expected to yield a positive result, thereby confirming that the experimental setup is functioning as intended. The positive control allows researchers to ensure that the test conditions are capable of producing a positive outcome when the experimental variable is applied.

In an experiment, having a positive control is essential because it helps to establish that any differences observed in other groups can be attributed to the experimental treatment rather than random chance or errors in methodology. For instance, if a researcher is testing a new drug, including a known effective drug as a positive control provides a benchmark against which the experimental results can be measured.

This clarity in results and methodology is vital for scientific investigation, as it enhances the reliability of the experiment's findings. In contrast, other options such as the test group, experimental group, or null hypothesis serve different functions and do not specifically represent a set of data expected to yield predictable positive results.