Concept:
This question tests the "Logic of Instructional Design." Every activity in a specific classroom (Biology) must serve the primary goals of that subject (Biology).
Step 1: Evaluating the Assertion.
Drawing is a powerful tool for visual learning. For a Biology teacher, "drawing a cell" is a perfectly valid instructional objective to ensure students recognize parts like the nucleus or mitochondria. Thus, A is correct.
Step 2: Evaluating the Reason.
It is a fact that drawing diagrams improves a student's general drawing skills. Thus, R is correct.
Step 3: Analyzing the Connection.
Does the Biology teacher set the objective *because* they want to turn students into artists? No. They set it because drawing helps students memorize biological structure. Therefore, while both are true statements, R does NOT explain the biological purpose of Assertion A.