A mutant strain of E. coli is found that produces ᵦ-galactosidase constitutively (constantly).
Which of the genotypes could cause this? (Note: lacP denotes the promoter for the lac operon)
A. P⁺I⁺O⁺Z⁺
B. P⁺I⁻O⁺Z⁺
C. Mutations in CRP-cAMP binding site.
D. P⁻I⁺O⁺Z⁺
E. More than one of the above.
F. None of the above.