Task: Class Definition Understanding (ontology: Earth_Environment/OBOE)

Which of the following definitions best describes 'SiemensPerMeter'?

A. A the concept is one nautical mile per hour, which is equal to exactly 1.852 km/h and approximately 1.151 mph.
B. A unit of concentration used for liquid-liquid solutions or for mixtures of gasses and of gasses and liquids.
C. Conductivity is the reciprocal (inverse) of electrical resistivity, ρ, and has the SI units of siemens per metre (S·m-1). "siemens" is used for both singular and plural.
D. Unit of concentration often used for gasses (e.g., oxygen, or O2) because it is related to solubility measurements.

Answer: Conductivity is the reciprocal (inverse) of electrical resistivity, ρ, and has the SI units of siemens per metre (S·m-1). "siemens" is used for both singular and plural.