In pavement design, how do CBR and modulus (k) differ?

In pavement design, how do CBR and modulus (k) differ?

• A. CBR is an empirical strength measure; modulus (k) is a stiffness parameter for structural design.
• B. CBR is a density measurement; modulus (k) measures soil color.
• C. CBR and modulus (k) measure the same property at different times.
• D. CBR is used for subgrade, modulus (k) for surfacing only.

Answer: (A)