Which description best captures good quality Bai Zhi?

• A. big single roots (not more then 36 roots/kg); greyish-surface; white, starchy cross section; intense, aromatic fragrance
• B. big single roots (not more then 36 roots/kg); greyish-brown or yellowish-brown surface; white, starchy cross section; intense, aromatic fragrance; no holes, black spots, or oil channels in its center
• C. many small roots; greyish surface; white cross section; intense fragrance
• D. short, fibrous roots; yellow surface; white cross section

Answer: (B)

Good quality Bai Zhi is judged by a combination of physical traits that reflect proper processing and potency: large, singular roots within a weight limit, a greyish-brown to yellowish-brown surface, a white and starch-filled cross-section, a strong, aromatic fragrance, and, crucially, no holes, black spots, or oil channels in the center. The best description matches all of these: big single roots (not more than 36 roots per kilogram), surface color in the greyish-brown or yellowish-brown range, white, white-starchy cross-section, intense fragrance, and absence of central defects. This combination indicates intact material that has been properly dried and stored. The other options either describe less ideal surface colors, altered interior characteristics, or root forms (many small roots, fibrous or short roots) that signal lower quality.