Answer: B. KL.
Step-by-step explanation:
A kiloliter (kl) is a unit which is derived from the metric SI (System International). This measurement is used when unit of volume with sides equal to one meter (1m) and as such, is equivalent to one cubic meter. One kiloliter (1kl) is which is same as one thousand liters (1000l). The kiloliter is used when volume of liquid is to be measured. This applies to a pool in the question.
