To determine which menu object property places a check mark in the display of the menu text, we need to understand the properties of menu objects and how they work.

The correct property that places a check mark in the display of the menu text is:

B. Checked

Explanation:

A menu object is used to create a dropdown menu or a contextual menu that contains a list of options for the user to choose from. The "Checked" property is used to indicate whether an option in the menu should be checked or not. When this property is set to true, a check mark will be displayed next to the menu item. If it is set to false, no check mark will be displayed.

Let's go through the other options to understand why they are incorrect:

A. Check: This is not a valid property for a menu object in most programming languages or frameworks.

C. CheckMark: This is not a valid property for a menu object in most programming languages or frameworks.

D. CheckOn: This is not a valid property for a menu object in most programming languages or frameworks.

E. RadioCheck: This is not a valid property for a menu object in most programming languages or frameworks. It might be a custom property specific to a particular framework or library.

Therefore, the correct answer is:

B. Checked