You have performed the following mating experiment using Hfr and F-strains of Escherichia coli: Hfr (thr⁺ leu⁺ gal⁺ strˢ) × F⁻ (thr⁻ leu⁻ gal⁻ strʳ). Which of the following selective media would you use to score recombinant colonies?
A) minimal medium B) minimal medium + streptomycin C) minimal medium + threonine D) minimal medium + streptomycin + threonine