The correct answer is b) Hilly regions.
Goat rearing is commonly practiced in hilly regions because goats are able to thrive in mountainous areas. They are sure-footed and can climb steep slopes, and they are able to survive on a diet of roughage and browse that is not available to other livestock. Goats are also relatively small and do not require a lot of space, which makes them well-suited for raising in hilly areas.
Coastal plains are not ideal for goat rearing because they are often wet and humid, which can lead to health problems for goats. Midland regions are also not ideal for goat rearing because they are often flat and have little vegetation, which means that goats have to be fed hay or other feed, which can be expensive. Backwater areas are not ideal for goat rearing because they are often flooded, which can drown goats.
In conclusion, goat rearing is commonly practiced in hilly regions because goats are able to thrive in mountainous areas.