All lipids are:
a) soluble in water
b) insoluble in water
c) contain a fatty acid
d) cholesterol

b) Insoluble in water  

Explanation:

Lipids or fats are water-insoluble organic molecules and soluble in certain organic substances such as alcohol, ether and acetone.

Lipids can be found in plant and animal foods and should be consumed in a balanced manner. These molecules have functions such as energy reserve, thermal insulation and vitamin absorption.

Lipids are esters, meaning they are composed of one acid molecule (fatty acid) and one alcohol molecule (glycerol or other). They are insoluble in water because their molecules are nonpolar, that is, they have no electric charge and therefore have no affinity for the polar molecules of water.