What characteristic is associated with prolific breeds of sheep?

Prolific breeds of sheep are primarily known for their ability to produce multiple births, which is a significant advantage in sheep production. This characteristic allows breeders to increase their flock size more rapidly and enhance overall productivity. Breeds that are classified as prolific, such as the Booroola Merino or the Romanov, often have a genetic predisposition to give birth to twins or triplets, making them particularly valuable for meat and wool production. The ability to produce multiple lambs per breeding season can positively impact the economics of sheep farming, as it allows farmers to maximize their yields and returns on investment.

While other characteristics such as feed efficiency, disease resistance, and wool quality may vary among different breeds, the defining attribute of prolific breeds is their capacity for higher numbers of offspring, making option B the correct choice.