What is the lifespan range for rats?

• A. 1-3 years
• B. 2-4 years
• C. 3-4 years
• D. 18-24 months

Answer: (B)

Lifespan in rats varies, but in biomedical and well-kept pet settings most live around 2–3 years, with some reaching about 4 years under good care. The range 2–4 years best reflects this typical variability, capturing the common lifespan span and allowing for longer-lived individuals across different strains and housing conditions.

Option outcomes to consider: living only 1–3 years would miss many rats that reach around 4 years. A 3–4 year range excludes the many rats that commonly live closer to 2 years. An 18–24 month range is too short for typical lifespans, since a substantial number live past 2 years.

So, the 2–4 year range is the most representative for rats in research and well-managed settings.