A) The operon is transcriptionally inactive in the absence of lactose.
B) The operon is transcriptionally inactivated by a repressor protein, which binds to glucose.
C) The operon is transcriptionally active when an activator protein binds to the promoter in the absence of glucose.
D) Glucose is the preferred energy source for E. coli.
E) The operon is repressed by its protein products.

A) DNA damage by UV light causes a λ lysogen to be induced to the lytic life cycle.
B) It is an error prone DNA repair system.
C) Activation of RecA by sensing DNA damage and single-stranded DNA.
D) Coordinated activation of a set of unlinked genes whose protein products will collectively help the cell to respond to environmental damage.
E) Transcriptional depression by proteolytic cleavage of the LexA repressor.