The term that best describes the number of organisms surviving long enough to be added to a population is "Recruitment." Here's why:
1. **Recruitment:** In biology and ecology, recruitment refers to the process by which new individuals (organisms) are added to a population through birth or migration. It focuses on the addition of individuals that survive and grow to be part of the population.
2. **Example:** For instance, in a population of fish, recruitment would involve the successful hatching and survival of fish larvae to become juveniles that contribute to the adult population.
Therefore, in the context of the question, "Recruitment" is the term that accurately describes the number of organisms surviving long enough to be added to a population.
