An entrance examination with objective type questions is conducted. For each correct answer, 1 mark is awarded and for each incorrect answer 0.25 marks are deducted. The number of marks scored by candidates who appeared in the examination is an example of:

Marks scored under this scheme form a discrete variable, taking only separated countable values in quarter-mark steps.

A nominal variable merely labels categories with no numerical order, unlike numeric scores.

An ordinal variable ranks categories but its intervals are not equal or arithmetically meaningful.

A continuous variable can take any value within a range, but these scores cannot fall between fixed steps.

With plus one and minus quarter scoring, totals jump by a quarter and never take intermediate values.

Discrete variables arise from counting, while continuous ones arise from measurement.