(will mark brainiest!)
Transgender is an umbrella term for persons whose gender identity, gender expression or behavior does not conform to that typically associated with the sex to which they were assigned at birth. . . . “Trans” is sometimes used as shorthand for “transgender.” While transgender is generally a good term to use, not everyone whose appearance or behavior is gender-nonconforming will identify as a transgender person. The ways that transgender people are talked about in popular culture, academia and science are constantly changing, particularly as individuals’ awareness, knowledge and openness about transgender people and their experiences grow.

Which statement best summarizes the central idea of the passage?

a) A person who identifies as transgender is either bisexual or homosexual.
b) Everyone with gender-nonconforming behavior is transgender.
c) A person with a gender-nonconforming appearance is bisexual.
d) The definition of transgender encompasses many people and is constantly changing.