Which factors are known to influence sexual orientation?

The correct answer focuses on biological and genetic influences on sexual orientation, which are important areas of research in understanding human sexual development. Studies have suggested that genetics can play a significant role in sexual orientation, as evidenced by various twin studies showing higher concordance rates for sexual orientation among identical twins compared to fraternal twins.

Birth order is another factor often cited in research, with some studies indicating that males with older brothers are more likely to identify as gay, potentially due to maternal immune responses that shift with successive pregnancies. Hormonal influences during prenatal development are also believed to affect brain structures that are linked to sexual orientation, contributing to differences observed between heterosexual and homosexual orientations.

In contrast, while the other options (social environment, education, parenting styles, peer pressure, personal experiences, culture, media influence, economic status, and friendship groups) may have roles in shaping individual experiences and social acceptance, they do not have the same level of scientific evidence linking them to the inherent aspects of sexual orientation itself. Factors like social environment and cultural influences can affect how individuals express their sexuality or how they are perceived by society, but they do not determine or influence the biological underpinnings of sexual orientation in the same way that genetics, birth order, and hormones do.