When conducting a semi-annual evaluation, what is the minimum number of IACUC members required to be present?

The correct answer highlights that in conducting a semi-annual evaluation, the minimum requirement is for two IACUC members to be present. This aligns with federal regulations, specifically the Animal Welfare Act and its corresponding guidelines, which stipulate that at least two members, including at least one scientist and one non-scientist, must convene for the evaluation to ensure compliance and adequate oversight of animal care and use within a research facility. The presence of these two members ensures that both scientific and ethical perspectives are represented, promoting a balanced evaluation of the program. This requirement supports the overall goal of maintaining high standards of animal welfare and research integrity.

The rationale against the other options is that having four members present or requiring all members to attend is not mandated by regulation for these evaluations, which allows for flexibility in scheduling and ensures that evaluations can occur efficiently while still meeting legal requirements.