You want to ensure that users have the information they need to make a reservation regardless of screen size. When viewed on a small screen, you do not need to display images.

Your assumptions are correct. Here are some more insights.

• A. Set the importance of the Make reservation column to Primary. This would put an emphasis on the checkbox on smaller screens. Since the restaurant's name is most arguably more important, this answer is not the best one.
• B. Set the importance of the Restaurant name column to Primary. At the very least, you want to expose the restaurant's name to users, even when using small screens. This is correct.
• C. Set the importance of the image column to Other. Other means that Pega is allowed to omit this piece of information on small devices. This answer is correct.
• D. Set the importance of the image column to Secondary. Secondary would still result in displaying the image on some tables and phones. The requirement was that images may be omitted, so this answer isn't the right one.
• E. Set the importance of the Restaurant location and Make reservation columns to Secondary. Correct. You want both pieces of information to be available. On smaller screens, primary will be displayed as header, while secondary columns are shown as list underneath.
• F. Set the importance of the Restaurant name and Make reservation columns to Primary. Only one primary column is allowed per table. This answer is incorrect.

Here's a visualization of how responsive breakpoints work as screen size shrinks: