Lymphoid tissue called Waldeyer's ring is situated in:
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).
Nasopharynx
Oropharynx
Both nasopharynx and oropharynx
Base of tongue
Nose and PNS