Which term refers to the classification of a person as male or female?

The correct choice pertains to the term that defines the classification of a person as male or female, which is gender. Gender encompasses the social and cultural roles, behaviors, and expectations associated with being male or female in a given society. This classification can include a range of identities beyond the binary understanding of male and female, reflecting how individuals may identify themselves in relation to societal norms.

Sex, in contrast, typically refers to the biological characteristics that differentiate males from females, such as reproductive anatomy and genetic differences. Orientation deals with the emotional, romantic, or sexual attraction one has towards others, and identity encompasses how individuals perceive and define themselves in a broader sense, which can include gender but is not limited to it. The specificity of gender in relation to the categorization of individuals as male or female makes it the most accurate choice in this question.