Examine the given diagram and respond to the following question.
* Triangle $\to$ Persons who drink tea
* Circle $\to$ Persons who drink coffee
* Rectangle $\to$ Persons who drink juice

How many individuals drink all three?

Refer to the file "image_b2c1a8.png" for the complete diagram and layout.

To find the number of individuals who drink all three beverages, we need to locate the region that is common to all three geometrical figures: the triangle (tea drinkers), the circle (coffee drinkers), and the rectangle (juice drinkers).
By examining the diagram in "image_b2c1a8.png":

* The number inside the region where the triangle, the circle, and the rectangle intersect simultaneously is $15$.

Therefore, there are $15$ individuals who drink all three.