Which one of the following is the duty of a class teacher?

A class teacher's charge extends across several parallel supervisory duties that operate together rather than as alternatives: keeping students academically prepared, monitoring their health and hygiene, and maintaining a clean, orderly classroom environment.

Applying this to the three specific practices named here: an unannounced check of notebooks and bags confirms academic preparedness, inspecting lunch boxes and advising healthier eating addresses student health and nutrition, and monitoring classroom cleanliness maintains the physical learning environment. Each of these is independently recognised as part of a class teacher's routine responsibilities, reflected in Kendriya Vidyalaya Sangathan's listed class-teacher duties and in CBSE's circular on lunch-box inspection and nutrition guidance.

• Picking only the notebook-and-bag check leaves out two other duties that are equally well documented.

• Picking only the lunch-box and nutrition check leaves out the material-readiness and cleanliness duties.

• Picking only the cleanliness check leaves out the academic and health-monitoring duties.

Since none of these three practices excludes the others, and each is a genuine part of the role, the option that names all three together is the only one that does not arbitrarily leave out a real duty.