Question

organic macromolecules called ______ are insoluble in water, are often found in biological membranes, and have the ability to store energy for extended periods of time.
a. carbohydrates
b. nucleic acids
c. lipids
d. proteins

Explanation:

Lipids are insoluble in water, are major components of biological membranes, and can store energy. Carbohydrates are water - soluble in many cases. Nucleic acids are involved in genetic information storage and transfer. Proteins have various functions but are not the main energy - storing insoluble molecules in membranes like lipids.

Answer:

C. lipids