Step 1: Understand what a base quantity is. A base quantity is a fundamental measurement that is not derived from other measurements.
Step 2: Learn about the SI system (International System of Units). It has seven base quantities: length, mass, time, electric current, temperature, amount of substance, and luminous intensity.
Step 3: Identify the options given in the question. You need to determine which one is a base quantity.
Step 4: Recognize that length is one of the seven base quantities in the SI system.
Step 5: Understand that force, energy, and pressure are not base quantities; they are derived from base quantities (for example, force is derived from mass and acceleration).
Step 6: Conclude that length is the correct answer as it is a base quantity.
