Concept: Teaching effectiveness depends on professional competencies that directly impact classroom learning.
Step 1: Evaluation of each factor
J: Subject knowledge ensures conceptual clarity and accuracy.
K: Socio-economic background does not influence teaching quality.
L: Communication skills ensure effective knowledge transfer.
M: Classroom management ensures organized learning environment.
Step 2: Elimination logic
K is irrelevant; J, L, and M are essential teaching competencies.
Step 3: Final conclusion
Thus, effective teaching depends on J, L, and M.