Is It as Effective to Take 2 Antibiotics Sequentially for an Infection

Is it as effective to take 2 antibiotics sequentially for an infection as it is to take them simultaneously, so long as the total length of time of the treatment is the same?

A) No. There's always one specific antibiotic that will be the most effective, and that is the only antibiotic that should be used to treat a particular infection.
B) Yes. So long as the length of time is the same, the 2 treatments should be essentially the same in terms of effectively eliminating the infection.
C) No. Taken sequentially, the first antibiotic will select for the small portion of the population that will spontaneously mutate towards resistance. Then, the second antibiotic will do the exact same thing-selecting for resistance to the second drug from the few bacterial cells that remained from the first drug treatment.
D) It depends. Provided that the majority of the infectious agent is killed off by the first drug, the likelihood that the few that are left would not also be killed by the second drug is low. However, simultaneous treatment should be more effective at eliminating all the microbes in the shortest time possible, and with the least probability of selection for multiple drug resistance mutations.