Which of the following scenarios depicts discrimination based on ancestry?

The scenario in which a sales agent named Aaron refused to rent an apartment unit to Nick Siriani specifically because of Nick's Italian surname clearly demonstrates discrimination based on ancestry. Ancestry discrimination occurs when individuals are treated unfavorably due to their family background, heritage, or ethnic traits. In this case, the action taken by Aaron directly correlates with Nick's surname, which serves as an identifier of his Italian ancestry.

Other options present forms of discrimination that do not focus specifically on lineage or ethnic background. For instance, refusing to sell to someone from a different state relates more to geographical discrimination rather than ancestry. Charging higher rent to non-native speakers targets language proficiency rather than the individual's ethnic heritage. Limiting showings to certain neighborhoods could entail various discriminatory motivations, such as socioeconomic status or race, but does not directly relate to ancestry as part of the decisive factor. Therefore, option B is the most clear and direct example of discrimination based on ancestry.