How many bits per pixel can be displayed with 4 bits of memory?

In digital imaging, the number of bits per pixel directly correlates with the number of colors or shades of gray that can be represented. With 4 bits of memory, each pixel can have 2^n distinct values, where n is the number of bits assigned to the pixel.

Using this calculation, 2^4 equals 16. This means that with 4 bits, we can represent a total of 16 different colors or shades of gray. Each combination of the 4 bits gives a unique value, allowing for a palette of 16 possible outcomes. This is foundational in understanding how digital images are constructed and displayed, especially in contexts like ultrasound imaging, where different shades can represent varying tissue densities or types.

Therefore, 16 bits per pixel is the correct representation for the situation described, reinforcing the principle of how bits translate to possible pixel values in digital imaging.