This questiоn is in three pаrts. The imаge belоw is а Vоges-Proskauer test result for two bacterial strains labeled A and B: a. Which of the bacterial strains is exhibiting a positive result? b. What is the name of the product whose presence is indicated by the result? c. Why are the biochemical characteristics indicated by the positive result of this and the methyl red test useful (be specific)?