Which statement correctly distinguishes scalar and vector quantities?

• A. Scalars have both magnitude and direction
• B. Vector quantities have only magnitude
• C. Scalar quantities have magnitude only
• D. Vector quantities have neither magnitude nor direction

Answer: (C)

Quantities in physics are either scalars or vectors based on whether they have direction in addition to size. Scalars are described by their magnitude only, with no direction attached. Examples include mass, temperature, time, and distance. Vectors, however, have both how much and which way — they have magnitude and direction — like velocity, displacement, and force.

So the statement that scalar quantities have magnitude only is correct because scalars are fully defined by how much there is, not by any orientation in space. The other options mix up the properties: scalars do not have direction, vectors do, and a vector cannot lack both magnitude and direction.