A streptomycin-sensitive Hfr strain, prototrophic for threonine (thr), leucine (leu), arginine (arg), and histidine (his), was allowed to conjugate with a streptomycin-resistant F- strain whose genotype was thr- leu- arg- his-. When plated on complete medium containing streptomycin, a number of colonies arose. Cells from five of these colonies were then tested on minimal medium supplemented with added nutrients as indicated below. What were the genotypes of the five colonies.