When the grade in a cloze multianswer questions contains a percentage value with decimal places, the percentage value is leaked to the question.

{5:MULTIRESPONSE_H:~%100%A~%50%B~%33.33333%C}

In this example the third answer reads

%33.33333%C

,which is unfortunate as it can give the right or wrong answer away to the student.
Removing the decimal places solves the problem, but then giving 1/3 of the points for an answer is not possible.
The above example was created with the Cloze editor that gives you 33.33333% as a selectable option.

To reproduce, create a cloze question, in the Atto editor use the cloze editor. Select MULTIRESPONSE_H, fill in answer and feedback and select a grade with decimal places. Insert and save changes. Then go to preview.