Correct Answer: Coagulation

Solution : The correct answer is coagulation.

When the suspended particles in any liquid solution form a precipitate and settle down, then this process is known as coagulation. The most common example of it is coagulation of blood which forms a blood clot and stops bleeding. Similarly when alum is added to the muddy water it reacts with the impurities of the water and forms a solid precipitate which settles down at the bottom of water along with all the suspended dust particles.