You notice that your roommate has swollen lymph nodes.Based on your knowledge of the lymphatic system,what might the clinical significance of this observation be?

A) Swollen lymph nodes may indicate the presence of an infection.
B) Swollen lymph nodes cannot be observed by a physical exam.
C) Swollen lymph nodes may signal the end of an illness.
D) Swollen lymph nodes are not clinically significant.