肠炎型犬细小病毒感染，犬腹泻，粪便呈（），最后由于心力衰竭和酸中毒而死亡。

A.灰黄色半固体

B.杨梅色液体

C.灰黄色液体

D.绿色液体

(31) analysis emphasizes the drawing of pictorial system models to document and validate both existing and/or proposed systems. Ultimately, the system models become the (32) for designing and constructing an improved system. (33) is such a technique. The emphasis in this technique is process-centered. Systems analysts draw a series of process models called (34) . (35) is another such technique that integrates data and process concerns into constructs called objects.

A．PERT

B．DFD

C．ERD

D．UML