Final answer:
The statement about rickets being 'usually genetic' is not true. Rickets is mostly caused by a deficiency in vitamin D which can lead to weak bones and skeletal deformities but can be prevented by sunlight and diet.
Step-by-step explanation:
The statement 'It is usually genetic' about rickets is not true. Rickets is typically caused by a deficiency in vitamin D, which is essential for the absorption of calcium and phosphate, necessary for healthy bone development. It is not commonly a genetic disorder, though there are rare genetic forms.
In children, it leads to weak bones and skeletal deformity such as bowing of the legs. Vitamin D can be synthesized by the body when the skin is exposed to sunlight, and it can also be obtained through diet and supplements. Therefore, both sunlight and dietary vitamin D are vital for preventing rickets.
Rickets is a childhood disorder characterized by bone deformities due to defective mineralization of bone. It is usually caused by a deficiency in vitamin D, which stimulates the intestinal absorption of calcium and phosphate.
Therefore, statement A, which says that rickets is usually genetic, is not true. Rickets can lead to weak bones, skeletal deformity, and is prevented by vitamin D and sunlight exposure.