Answer:
The correct option is;
C. The intensity control
Step-by-step explanation:
The trace is the visible lines displayed on a CRT formed by the electron beam movement.
The brightness of the displayed trace can be adjusted by increasing or reducing the intensity control as the sweep of the analog oscilloscope is increased or decreased
The sweep of an oscilloscope is an indication of the speed with which the trace is allowed to sweep across the screen of the oscilloscope while being visible. The sweep is measured in seconds per division.