Here's a problem to solve: In which way is any single observation of wind speed best described?

Among the 4 following options, which is the correct answer?

- A: It is an indication of a future weather condition.
 
- B: It is an indication of the amount of humidity.
 
- C: It is an indication of weather at a specific time.
 
- D: It is an indication of the existing climate.
 