Which of these values could be slope of the line?

Suppose a man is heterozygous for heterochromia, an autosomal dominant disorder which causes two different‑colored eyes in an individual, produced 25‑offspring with his normal‑eyed wife. of their children, 15 were heterochromatic and 10 were‑normal. calculate the chi‑square value for this observation.

When y’all answer can y’all explain too !

Pranza plotted point a in the coordinate plane below.