To determine which number represents only 'Shirts and Pants' in the Venn Diagram, we need to analyze the sections where the sets overlap.

The shapes represent the following:

• Rectangle: Shirts
• Circle: Pants
• Triangle: Trousers

Analyzing the diagram:

• Region labeled with '5': This region is at the intersection of the rectangle (Shirts) and the circle (Pants), but not within the triangle (Trousers). Therefore, it represents only 'Shirts and Pants'.

The other options can be ruled out as follows:

• Region labeled with '1': This is at the intersection of all three shapes (Shirts, Pants, and Trousers).
• Region labeled with '30': Falls within both rectangle (Shirts) and triangle (Trousers), but outside the circle (Pants).
• Region labeled with '15': This is at the intersection of the circle (Pants) and the triangle (Trousers), but not in the rectangle (Shirts).

Conclusion: The number that represents only 'Shirts and Pants' is 5.