A bicycle pump's outlet is blocked and its piston is pushed in slowly, so the trapped air stays at room temperature. Evaluate the Assertion (A) about the air's pressure and the molecular Reason (R) offered for it.

• Assertion (A): When the trapped air is compressed at constant temperature, its pressure increases.
• Reason (R): The number of molecules per unit volume increases, so molecules strike each unit area of the walls more often.