Are cellular macromolecules containing hydrogen, oxygen, nitrogen, carbon and phosphorous.
a. fatty acids
b. nucleic acids
c. simple sugars
d. complex carbohydrates

The correct answer is option B, Nucleic acid.

Explanation:

A nucleic acid is made of chain of structural repeating units called nucleotide. Each nucleotide consists of  nitrogen atom attached to a pentose ( five carbon) sugar which is further attached to a phosphate group. A sugar is nothing but a macro molecule that is made up of carbohydrates consisting of carbon, hydrogen and oxygen.  

Thus, it can be said that a nucleic acid is made up of  

a)Carbon,  

b)Nitrogen,  

c)Hydrogen  

d)Oxygen and

e)Phosphorus

this protocol provides a detailed procedure for co-immunoprecipitation (co-ip) to identify protein–protein interactions.