Final answer:
Technician A may not be accurate as a faulty flasher unit would typically affect both turn signal directions. Technician B's proposal that the fuse is blown is more likely, as fuses can be specific to one direction's circuit but other functions might also be affected.
Step-by-step explanation:
When a car's turn signals operate in one direction only, it typically indicates a problem within the turn signal circuit. If it were an issue with the flasher unit, both directions would likely be affected, not just one. Therefore, Technician A's suggestion that the flasher unit is bad might not be entirely accurate. On the other hand, if there were a problem with a fuse, it might be on a circuit dedicated to one direction of the turn signals. Hence, Technician B's hypothesis that the fuse might be blown could be plausible. However, it's important to note that fuses often control more than one function, so other electrical problems might be present if a fuse were blown.