Final answer:
Treating both partners simultaneously is important in preventing reinfection and the spread of Trichomonas vaginalis.
Step-by-step explanation:
The best statement that indicates that the client has learned measures to prevent a recurrence of Trichomonas vaginalis is option B: My partner must get treated before we have sex again. Treating both partners simultaneously is important in preventing reinfection and the spread of the infection. It ensures that both partners are free from the parasite and reduces the risk of reinfection.