Final answer:
The odometer in an automobile indicates a scalar quantity because it measures distance traveled without direction. Scalar quantities have magnitude only, whereas vector quantities include both magnitude and direction. For an automobile, speed is a scalar quantity while velocity is a vector quantity. Hence, option (c) is correct.
Step-by-step explanation:
The odometer in an automobile indicates a scalar quantity because it measures the total distance traveled without regard to direction. Distance as indicated by an odometer only has magnitude and does not incorporate any element of direction, which is a key component of a vector quantity. Therefore, the correct answer is a) Scalar - Only magnitude.
When discussing vector quantities, direction is a crucial component along with magnitude. For example, velocity is a vector quantity because it includes both speed and the direction of movement. This contrasts with the concept of speed, which is measured by a car's speedometer, and is a scalar quantity because it represents how fast the car is traveling irrespective of the direction.
It's worth noting that displacement, which does involve direction, can be the same as distance if the starting and endpoint are the same, however, in real-life scenarios such as driving a car, the odometer measures the total distance rather than the displacement.