What is the formula for calculating image file size?

The formula for calculating image file size incorporates the dimensions of the image and the color depth. The correct choice specifies that file size is determined by multiplying the width and height of the image by the color depth, which represents the number of bits used to indicate the color of a single pixel.

Multiplying width by height gives the total number of pixels in the image. By including the color depth in the formula, you account for the amount of data each pixel occupies. However, since file sizes are typically measured in bytes, it is necessary to divide by 8, as there are 8 bits in a byte. This conversion ensures that the result is in the appropriate unit of measurement for file size.

So, the complete formula reflects this relationship:

File size = (width × height × color depth) ÷ 8

This ensures that the calculated size corresponds accurately to how digital storage measures image files, making option C the correct choice.