I believe it would be (B) but i’m sorry if i am wrong.
Genetic drift is defined as a shift in the allelic frequency of a population. This can be caused by natural selection which is the differential survival and reproduction of individuals across a population due to differences in phenotype. Natural selection favors particular traits in a population hence these individuals are able to reproduce while the individuals with disadvantageous traits will pass their genes to succeeding generations. This way the allelic frequency of succeeding generation will be diferent from that of the parent population.
Operons afford the organism the opportunity to
simultaneously regulate transcription of multiple genes, whose products are
active in the same process. Operons lead to the synthesis of groups of functionally
related enzymes, usually from a single mRNA transcript hence makes regulation of
the genes highly efficient.
Active transport.
Passive transport, being its opposite, requires no energy at all. Therefore, active transport would require energy or ATP in order to move across.
Hope this helps!