If an esthetician performs pétrissage three times on the left side of a client's neck, s/he should perform _________.

The best choice is to perform pétrissage three times on the right side of the client's neck after having done the same technique on the left side. This approach maintains balance in the treatment, ensuring both sides of the body receive equal attention and stimulation.

Pétrissage, which involves kneading and rolling movements, is designed to enhance circulation and relieve muscle tension. By utilizing the same technique on both sides, the esthetician provides a uniform experience that promotes symmetry in treatment.

In contrast, other options introduce different types of techniques or unequal focus on one side, which may disrupt the flow of the treatment. For instance, performing tapotement immediately after pétrissage alters the therapeutic effect and may not be appropriate following this particular technique. Similarly, doing effleurage on one side does not address the need for equal treatment on both sides, which can lead to a lack of balance in application.