Which test among the following assesses lower body strength?

The chair stand test is specifically designed to assess lower body strength, which is crucial for maintaining mobility and independence in seniors. This test involves timed repetitions of standing up from a seated position and sitting back down, typically performed with a standard chair. It directly measures the strength of the muscles in the legs, hips, and core, which are essential for daily activities such as standing up, walking, and climbing stairs.

In this context, the other options do not focus on lower body strength. The back scratch test evaluates flexibility in the upper body, specifically the shoulders and back. The 2-minute step test measures cardiovascular endurance and aerobic capacity by assessing how many steps one can take in a predetermined time. Height and weight measurements are used to determine body composition and overall health but do not provide any insight into lower body strength. Thus, the chair stand test is the appropriate choice for assessing lower body strength among the listed options.