The four remarkable classics in TCM history are_________.

A、Huangdi’s Internal Classic, Pulse Classic, The Classic of Difficulties,
Shennong’s Classic of Materia Medica
B、Huangdi’s Internal Classic, The Classic of Difficulties, Shennong’s Classic of Materia Medica, A-B Classic of Acupuncture and Moxibustion
C、Huangdi’s Internal Classic, The Classic of Difficulties, Treatise on Cold Damage and Miscellaneous Diseases, Shennong’s Classic of Materia Medica
D、Huangdi’s Internal Classic, The Synthesis of Chinese Medicine, The Classic of Difficulties, Shennong’s Classic of Materia Medica