How many mugs are not plate?

1. Identify the shapes corresponding to the categories: Triangle = Mugs, Horizontal Rectangle = Plates.
2. Locate all the numbers strictly inside the 'Mugs' region (Triangle): 3, 9, 4, and 6.
3. Exclude any numbers that fall inside the 'Plates' region (Horizontal Rectangle), which are 9 and 4.
4. Sum the remaining numbers: 3 (Only Mugs) + 6 (Mugs and Cups) = 9.
Final Answer: Option C