###Rationale: Waldeyer's ring consists of subepilhelial collection of lymphoid tissue. It comprises adenoid, tubal tonsil (both in nasopharynx) and palatine tonsils, lingual tonsils and granules in posterior pharyngeal wall (in oropharynx).

###Answer: OPTION C IS CORRECT.
###Question: Lymphoid tissue called Waldeyer's ring is situated in:
###Options:
A. Nasopharynx
B. Oropharynx
C. Both nasopharynx and oropharynx
D. Base of tongue
