Properties of Vector Physical Quantities

Steps:

• Physical quantities represent measurable properties in physics.
• They are categorized as scalars (magnitude only) or vectors (magnitude and direction).
• Vectors, like force or velocity, require direction to specify complete information.
• All quantities need standard units for quantification and comparison.

Why C is correct:

• Vector quantities are defined by having both magnitude and direction (as in the vector addition law), and units are required by the International System of Units (SI) for all measurements.

Why the others are wrong:

• A: Identical to C, but if intended for scalars, it wrongly includes direction.
• B: Omits direction, which vectors must have to distinguish from scalars.
• D: Excludes magnitude, leaving only units, which cannot define a quantity alone.

Final answer: C