What might a "tangible" event involve?

A "tangible" event refers to something that can be perceived through the senses, particularly something that is real and substantial in nature. Therefore, it involves visible and concrete aspects that can be directly observed or interacted with. This might include physical activities, ceremonies, or gatherings that are observable and have a material presence in the world. The essence of the term “tangible” implies that the event has a definite form or reality that can be experienced firsthand, as opposed to being abstract or purely conceptual.

In contrast, the other options suggest qualities that are non-physical or not directly observable, which do not align with the meaning of "tangible." Thus, the choice of visible and concrete aspects effectively captures the correct interpretation of a "tangible" event.