Which of the following are the reasons for the blurring of the monitoring screen? (Multiple Choice)

Which of the following are the reasons for the blurring of the monitoring screen? (Multiple Choice)
A . The lens aperture size is inappropriate
B . Influence of noise reduction intensity
C . Incorrect lens focal length or inaccurate focus
D . The surface of the lens is dirty or there are water stains, dust etc.

Answer: ACD