China's first moon rover, Yutu, or Jade Rabbit touched the lunar surface at 9:14 a.m.on December 14,2013,  ________deep trace on the loose lunar soil.

A．left

B．leaving

C．Having left

D．To leave

以下哪项疾病可引起口腔黏膜色素沉着（）

A.缺铁性贫血

B.血小板减少性紫癜

C.原发性慢性肾上腺皮质功能减退

D.维生素C缺乏症

E.糖尿病