Refer to the Table Showing a Hypothetical Data Set Comparing

Multiple Choice

Refer to the table showing a hypothetical data set comparing the gene content of strains of Salmonella and Shigella (which are all pathogenic) and pathogenic and nonpathogenic strains of E.coli.(Note: "x" denotes presence of the gene.) What is the most likely conclusion about gene A?

A) It may be involved in pathogenicity and was acquired from Salmonella strain 1.
B) It may be involved in pathogenicity and was acquired from Salmonella strain 2.
C) It may be involved in pathogenicity and was acquired from Shigella.
D) It may be involved in pathogenicity, and its origin is unclear.
E) It is unlikely to be involved in pathogenicity.