Which range best reflects the Recommended Dietary Allowance (RDA) for protein intake in healthy adults?

• A. $0.2–0.3$ g protein per kg body weight per day
• B. $1.6–2.2$ g protein per kg body weight per day
• C. $3.0$ g protein per kg body weight per day for all adults
• D. $0.8$ g protein per kg body weight per day (approximately $46$ g/day for most women and $56$ g/day for most men)

Answer: (D)