What does blurring/smoothing do?

• A. Reduces noise
• B. Increases sharpness
• C. Changes color
• D. Offsets exposure

Answer: (A)

Blurring and smoothing primarily reduce noise by averaging neighboring pixels. This process smooths out random variations in intensity that make an image look grainy, especially in low-light or high-ISO photos. Because it combines nearby pixel values, high-frequency details and edges get softened, leading to a smoother overall look. It doesn’t make an image sharper, nor does it purposefully change color or adjust exposure—those are separate operations. So the main effect is dampening noise through averaging, which is why reducing noise is the best description.