You made a cup of coffee for your father. So, you put sugar, coffee, and creamer in warm water and stirred them well until no solid was visible. After your father had left his coffee, you noticed that the creamer clumped together and formed residues in the cup. What type of mixture did you prepare and why?

a.
A homogeneous mixture since sugar, coffee, and creamer were mixed well and no clumps of solid were visible when served

b.
A heterogeneous mixture since the mixture of sugar, coffee, and creamer appears as a single phase, and suspended particles of the creamer were seen afterwards.

c.
A heterogeneous mixture since the sugar, coffee, and creamer were still in the warm water, even if there was only one visible phase, they could still be separated.

d.
A heterogeneous mixture since in making a cup of coffee, three visible layers were present - sugar, coffee, and creamer.​