What is a control?

a variable or variables that you must keep constant during an experiment

a variable or variables that you manipulate during an experiment

a variable or variables for which you cannot account

a variable or variables that change with the independent variable

Respuesta :

Answer:

a is the answer

please mark it brainliest

Answer:

A control variable (or scientific constant) in scientific experimentation is an experimental element which is constant and unchanged throughout the course of the investigation.

Explanation: