Final answer:
The recommended position for postural drainage of the right upper lobe - anterior lung segment in an adult is left side-lying.
Step-by-step explanation:
The recommended position for postural drainage of the right upper lobe - anterior lung segment in an adult is B) Left Side-Lying.
Postural drainage is a technique used in respiratory therapy to help mobilize secretions and improve lung function. In this position, gravity helps to promote drainage of secretions from the right upper lobe - anterior lung segment.
By lying on the left side, the patient allows the right upper lobe to be positioned in an upward direction, allowing for easier drainage of secretions.