Answer:
D
-----------------------------------------------------------------
The definition of colloids is very disputed on whether or not it is homo/heterogenous. I wouldn't go with this answer, but its based on what you learned it was. At a microscopic level its hetero but at a macroscopic its homo.
They do have somewhat large dispersed particles but this better describes suspensions
They don't easily settle out.
And in order to be a mixture, they are made up of at least two substances
D is likely the best answer out of the bunch.
