The correct option for the question "Selection based on the performance of ancestors is referred to as" is B. pedigree selection. Detailed Explanation 1. Understanding Pedigree Selection: Pedigree selection is a breeding method that focuses on the genetic background of an organism, particularly its ancestors. This method involves evaluating the performance of the ancestors (parents, grandparents, etc.) to predict the potential performance of their offspring. The idea is that if the ancestors have desirable traits (like high yield, disease resistance, or good quality), these traits are likely to be passed down to the next generation. 2. Why Pedigree Selection is Correct: - Genetic Basis: Pedigree selection relies on the principle of heredity, where traits are passed from one generation to the next. By studying the performance of ancestors, breeders can make informed decisions about which individuals to select for breeding. - Performance Records: In pedigree selection, breeders often keep detailed records of the performance of each ancestor, which helps in assessing the likelihood of producing superior offspring. - Long-term Improvement: This method is particularly useful for long-term breeding programs, as it allows for the selection of traits that may not be immediately visible in the current generation but are evident in the lineage. 3. Why Other Options are Incorrect: - A. Family Selection: This method involves selecting a group of related individuals (a family) based on their collective performance rather than focusing solely on the performance of ancestors. Family selection looks at the average performance of a family rather than individual ancestors, making it less specific than pedigree selection.

• C. Progeny Selection: Progeny selection is based on the performance of the offspring rather than the ancestors. In this method, breeders evaluate the traits of the offspring produced by selected parents to determine which individuals should be retained for future breeding. This is a more immediate approach and does not focus on the historical performance of ancestors.
• D. Line Selection: Line selection refers to the selection of specific lines or strains within a species based on their performance. While it may consider some ancestral traits, it is more about the performance of a specific breeding line rather than the broader ancestral performance that pedigree selection emphasizes.

Summary of Key Points

• Pedigree Selection focuses on the performance of ancestors to predict offspring traits.
• It is based on the principles of heredity and requires detailed performance records of ancestors.
• Family Selection looks at the collective performance of related individuals, while Progeny Selection evaluates offspring performance.
• Line Selection focuses on specific breeding lines rather than ancestral performance.

Revision Summary

• Pedigree selection evaluates ancestors' performance to predict offspring traits.
• It is a long-term breeding strategy based on genetic inheritance.
• Other selection methods (family, progeny, line) focus on different aspects of breeding.
• Understanding these distinctions is crucial for effective breeding program design.