About the level represented by the characteristics of "high-low-high-low-high" echo in the wall of the stomach from the inside to the outside, what is wrong is ( ). A: mucosal surface and interface B: mucous muscularis C: submucosa D: the muscularis propria E: Interface and serosal layer

What is the outermost layer of the GI tract called? A: Mucosa B: Sub mucosa C: Muscularis D: Adventitia

下列字母组合sc的发音是[∫]的是 A: scabies B: fuscus C: scientia D: muscularis