Which of the following disorder is not hereditary?

The correct option is B Cataract

A. Haemophilia is a X-linked recessive genetic disorder that occurs due to deficiency of clotting factors in the blood and therefore, there is no formation of clot at the site of wound.

B. Cataract is an eye disease that occurs in older people. The visibility is reduced because the eye lens becomes opaque. It is treated by surgery.

C. Sickle cell anaemia is a autosomal recessive genetic disorder in which red blood cells become sickle shaped and this causes oxygen tension in the body.

D. Colour blindness is a X-linked genetic disorder in which there is inability to distinguish colours due to defect in cones (photoreceptor cells associated with daylight vision and colour vision).

Hence, cataract is not hereditary because it is not a genetic disorder.

So, the correct answer is 'Cataract'.