Changing Gender Field Options

I’m putting-together a site based on the Dating theme for a hard-core religious group, and when they saw that “Group” and “Couple” were among the gender options, I assured them, “I’m sure I can get rid of those choices” (thinking it was just a configuration setting).

I found a previous thread (https://www.premiumpress.com/forums/topic/editing-built-in-custom-fields/) that talks about how new options can be added, but for the life of me, I can’t figure-out how to get-rid of (or change) the “built-in” ones.

Thanks in advance for any help!