Mass determines inertia

Steps:

• Note that mass of P exceeds mass of Q, as stated.
• Recognize "amount of matter" as mass.
• Identify "resistance to change of motion" as inertia.
• Recall inertia is directly proportional to mass, so P has greater inertia.

Why A is correct:

• Inertia is the property of mass to resist acceleration, per Newton's first law.

Why the others are wrong:

• B: Q has smaller mass, not greater.
• C: Q has smaller inertia due to less mass.
• D: Q has neither greater mass nor greater inertia.

Final answer: A