Most children have developed a firm gender identity by . . . a. 6 months. b. 12 months. c. 18 months. d. 3 years.

d. 3 years

Explanation: Gender identity is a personal sense of what gender an individual is. It may or may not be the same thing as the gender registered at birth. Before age 3, children hardly notice the differences but at this age, they are aware of their environment and the basic differences between the two genders.

At this age, most children identify as their birth gender as they learn from the environment their gender expectations; from their family, school,religious organisations; and they are aware of the fundamental differences between the genders.