Final answer:
The compressive strength of a specimen is calculated by the load divided by the cross-sectional area, which is option A.
Step-by-step explanation:
The compressive strength of a specimen is calculated by dividing the load attained during the test by the cross-sectional area of the specimen. Therefore, the correct answer to the question is option A: Load, Cross-sectional area. When calculating the compressive strength, the load is the force applied to the material, and the cross-sectional area is the area over which this force is distributed.
Density is the mass per unit volume of a substance and is typically measured in kilograms per cubic meter (kg/m³). Pressure, on the other hand, is the force per unit perpendicular area and is measured in pascals (Pa). In the context of determining compressive strength, we focus on the applied load and the area it affects.