If an apostrophe (ASCII character 39) is entered into a short answer field of a multianswer (cloze) question, and the answer is then either submitted individually (using the adaptive mode) OR saved without submitting with other answers displayed on a quiz page, there is a backslash character inserted in front of the apostrophe each time the quiz page is reloaded.
Example:
[SHORTANSWER FIELD]: Boys' Orchestra

• Save without submitting (1)
  [SHORTANSWER FIELD]: Boys\' Orchestra
• Save without submitting (2)
  [SHORTANSWER FIELD]: Boys\\\' Orchestra
• Save without submitting (3)
  [SHORTANSWER FIELD]: Boys\\\\\\\' Orchestra

What I did was to add a stripslashes() into the question\type\multianswer\questiontype.php file – as shown below. I do not know though whether I should consider this solution systematic or robust enough.

— ORIGINAL question\type\multianswer\questiontype.php Sat Sep 23 16:52:53 2006
+++ MODIFIED question\type\multianswer\questiontype.php Sat Sep 23 17:35:33 2006
@@ -304,7 +304,7 @@
case 'shortanswer':
case 'numerical':
echo " <input $style $readonly $popup name=\"$inputname\"

• type=\"text\" value=\"$response\" size=\"12\" /> ";
  + type=\"text\" value=\"".stripslashes($response)."\" size=\"12\" /> ";
  break;
  case 'multichoice':
  $outputoptions = '<option></option>'; // Default empty option