Answer:
a. set of recorded values of variables associated with a single entity.
Step-by-step explanation:
Observation is an active acquisition of the information from any primary source. In living beings, the observation employs senses. It is important as observations lets us find the unexpected things around us which may stimulate the curiosity of ours and leads to a new experiment. It is the recorded values of the variables that is associated with any single entity.
Hence the correct option is (a).