How do colloids that exist in nature affect people

The exposure of a person to colloids majorly present in industrial area may results in the accumulation in the body tissue which causes dark deposit in the skin. They are not safe and is dangerous for health which may cause turning of skin blue permanently and it is life long.

Whereas, the colloid of silver nitrate is used to treat skin burns and ulcers but its overuse may result in adverse effect.

i'm assuming that the correct answer is indeed the first one/ "a"..

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.