Concept:Beef cattle are raised for meat production, whereas butter-fat percentage relates to dairy cattle.
Explanation:In beef cattle breeding, the main goal is to improve meat yield and quality.
High fertility is important because it allows the herd to reproduce efficiently.
Good feed conversion efficiency is also vital, as it reduces the cost of producing meat.
A high yield of lean meat is directly desirable in beef cattle.
Increased butter-fat percentage, however, is a trait valued in dairy cattle for milk and butter production.
It is not a key characteristic in beef cattle breeding.
Answer:B. increased butter-fat percentage