Final answer:
Race is a social construct without biological grounding; genetic markers do not align with racial classifications, making set guidelines or tests for determining race scientifically untenable. The use of physical traits like skin color for racial categorization is inaccurate, and the concept of a 'biologically pure race' is unfounded.
Step-by-step explanation:
None of the statements provided are true, as race cannot be scientifically determined through set guidelines or tests. The concept of race is not biologically valid because genetic variation is more significant within racial categories than between them. Anthropological research, including studies by Agustín Fuentes and Nina Jablonski, has shown that traits such as skin color and facial features vary on a spectrum and do not segregate people into discrete biological groups.
Furthermore, American racial categories relying on skin pigmentation, hair texture, and eye shape – the "three-factor test" – are social constructions rather than scientific classifications. The use of such categories can lead to discrimination, whereas a focus on ancestry, rather than race, could offer a more nuanced understanding of human genetic diversity. Historical perspectives also reveal that the definition of race has evolved, aligning more with physical characteristics over time.