Answer:
Allowing the organism to adjust to changes in environmental conditions.
Explanation:
Gene may be defined as the functional segment of the DNA that codes for the particular protein and responsible for the genotype and phenotype expression of the organisms.
The gene expression of the particular genes can be modified according to the activity and the external environment of the organism. The altered expression of gene is important as it helps the prokaryotic organism to adapt better in their environment.
Thus, the correct answer is option (b).