Which statement describes the biennial surveillance interval?

Which statement describes the biennial surveillance interval?

• A. biennial
• B. 12 years
• C. 30 months
• D. 6 weeks

Answer: (A)

Biennial describes a frequency of every two years. In surveillance scheduling, using the term biennial means the interval is about 24 months between checks. The statement that is simply “biennial” matches that two-year cadence exactly. The other durations—12 years, 30 months (2.5 years), and 6 weeks (about 1.5 months)—do not equal two years, so they don’t describe a biennial interval.

Biennial describes a frequency of every two years. In surveillance scheduling, using the term biennial means the interval is about 24 months between checks. The statement that is simply “biennial” matches that two-year cadence exactly. The other durations—12 years, 30 months (2.5 years), and 6 weeks (about 1.5 months)—do not equal two years, so they don’t describe a biennial interval.