Is the visual effect caused by an object's absorption of certain portions of the visible light spectrum and transmission or reflection of others.
a) dispersion
b) color
c) density
d) refractive index

B) Color

Explanation:

The visible light spectrum is a part of the electromagnetic spectrum, as its name says it is the part of the spectrum that we can see.

The visible light spectrum is made up of a wavelength range of approximately 450nm to 700nm, ranging from violet to red.

This is why the wavelength determines color, when an object absorbs a portion of the visible light spectrum and reflects the rest, for us as an observer we only see the part of the visible light spectrum that reflects and this is what determines the color of the things we see around us.

The answer is:

Color is the visual effect caused by an object's absorption of certain portions of the visible light spectrum and transmission or reflection of others.

real, smaller and upside-down.   so the answer should be b.