​To Measure How Well a Child Can Resist Temptation,which Procedure

Multiple Choice

​To measure how well a child can resist temptation,which procedure have psychologists often used?

A) "Draw a pretty picture, but don't look at what any other children are drawing."
B) ​"I'm leaving the room now, but please sit quietly in your seats until I return."
C) ​"Answer these questions, but please don't look at the answer key on the back of the page."
D) ​"Here is one marshmallow, but if you wait you can have two."