Verified Answer :

Answer:

C. Length: km

Explanation:

Let's analyze each option:

A. Mass: in the SI system, mass is measured in kilograms (kg), so this matching is correct.

B. Time: in the SI system, time is measured in seconds (s), so this matching is correct.

C. Length: in the SI system, length is measured in meters (m). The kilometer, instead, is a multiple of the meter (\(1 km = 1000 m\)). Therefore, this matching is not correct.

D. Temperature: in the SI system, temperature is measured in Kelving (K), so this matching is correct.