The issue of classifying people's sexual orientations is made difficult by the fact that: a. a relatively high percentage of people report same-gender attraction, yet do not identify themselves as homosexual or bisexual. b. there are substantially more people who self-identify as homosexual than as bisexual. c. homosexuals and bisexuals constitute such a small proportion of the population d. there are substantially more people who self-identify as bisexual than as homosexual