Use OTDR to locate the position of abnormal attenuation in the optical path. After the OTDR connection is to be detected the line, which of the following parameters can be set? (Multiple Choice)

Use OTDR to locate the position of abnormal attenuation in the optical path. After the OTDR connection is to be detected the line, which of the following parameters can be set? (Multiple Choice)
A . Set the measurement range
B . Set the wavelength
C . Set the mode
D . Set the pulse width

Answer: ABCD