Well Carl Linnaeus was the guy who classified the different species of organisms into categories and gave them a Latin name for the Genus and Species. So I would say classification of organisms.
The variable that records the exact time at which each probationer has arrived is a continuous variable.
When a variable is continuous, it means that there is an infinite number of possible values. Times are measured by decimal numbers with can present infinit values because, for instance, one subject might arrive at 2pm 30min 24,01 seconds and the following at 2pm 30min 24,00001 seconds.
One the other hand, a finite number of values is available in discrete variables. For example, a variable measuring the gender of the subjects is discrete because it contains only two possible values: man/woman.
Hey You!
As the old clichè claims, the three most important things in retailing are: Location, location, and location.
(It should be option C on your sheet or device).