On ________ Monday morning in July，Mr. Anderson happened to find his missing father among the people at ________ church.

A．a；the

B．the；/

C．a；/

D．/；a

滴眼剂中加入氯化钠的作用是（）。

A．调节渗透压 

B．调节pH值 

C．调节黏度 

D．抑菌防腐 

E．稳定剂