The Patient Had Knee-Replacement Surgery and Has a Local Infusion

The patient had knee-replacement surgery and has a local infusion pump to provide a local anaesthetic to the surgical site.The patient puts on the call light and complains that pain at the site is more intense than it has ever been and is getting worse.The nurse checks the site and finds that the dressing is damp but intact.The infusion pump is pumping,and there is medication in the bag.The most probable cause of the problem might be the

A) catheter may be clogged.
B) pump may be releasing too much medication into the site.
C) catheter may be displaced.
D) patient may be exaggerating the pain.