Which is the earliest extant Chinese materia medica text, compiled in the Eastern Han Dynasty, focusing on description of individual herbs?
选项：

A:Shen Nong Ben Cao Jing (Shen Nong’s Classic of the Materia Medica)
B:Ben Cao Jing Ji Zhu (Collection of ‘Commentaries on the Classic of the Materia Medica)
C:Xinxiu Bencao (Newly Revised Materia Medica)
D:Ben Cao Gang Mu (Compendium of Materia Medica)