{{B}}quEstions 16 to 20 ArE BAsED on thE Following tAlk.{{/B}}

A、it is ADvisED For ExtrEmE pAin only.
B、it is ADvisED For pAin lAsting morE thAn two DAys.
C、it is ADvisED For A mAximum oF two DAys.
D、it is ADvisED whEn onE is unABlE to holD his or hEr spinE.