An elderly client with Alzheimer's disease begins supplemental tube feedings through a gastrostomy tube to provide adequate calorie intake. The nurse should be concerned most with the potential for （）.

A．hypoglycemia.

B．fluid volume excess.

C．aspiration.

D．constipation.

洞室顶拱部位有如图所示的被裂隙围限的四个区，( )区有可能是不稳定楔形体区。 （）

A．(A) ①

B．(B) ②

C．(C) ③

D．(D) ④