None of these! I assume the answer your instructor is looking for is maxing out. It’s the most effective option, but also the one with most risk.
However, the best way and frankly the gold standard way to asses muscular strength is via a maximal voluntary isometric contraction using a dynamometer. No weights need to be selected here, it’s your muscle isometrically contracting at a specific joint angle for 3-5 seconds. Usually 3 attempts are required. The highest force output in Newton’s is recorded as max strength.
