Proper application of content knowledge is evident when the teacher:

Concept: Effective teaching requires more than possessing subject-matter (content) knowledge alone — it requires Pedagogical Content Knowledge (PCK): the ability to transform that content, through analogies, representations, examples, and sequencing, into a form that is accessible and meaningful to learners at their level of understanding (Shulman, 1987).

Application: The stem asks which teacher behaviour demonstrates "proper application of content knowledge" in practice. The option stating that the teacher "transforms the subject matter in such a way that it reaches the students" directly describes this act of reshaping content for learner accessibility — the defining feature of PCK.

Cross-check — contrasting the other options by value:

• Giving a lot of home assignments changes the QUANTITY of practice students do outside class; it does not describe reshaping the subject matter itself.

• Explaining the topic clearly is a delivery/communication quality; being clear does not by itself mean the content was restructured into a form matched to learners' understanding.

• Giving adequate notes supplies written reference material; it does not describe transforming the subject matter itself for learner accessibility.

Result: Therefore, "transforms the subject matter in such a way that it reaches the students" is the option that correctly describes proper application of content knowledge.