Final answer:
A diagonal line over a symbol suggests dynamic relationships: in art, it conveys movement; in math, it connects points on a graph; and in pedigrees, it connects parents to offspring.
Step-by-step explanation:
A diagonal line over a symbol in various contexts can denote different things, but generally, it indicates some sort of movement or a relationship between variables. For example, in the context of art, as noted with Bernini's David, a diagonal line suggests movement, energy, and drama. In contrast, horizontal lines often imply calmness and vertical lines stability. In a more mathematical context, diagonal lines on a graph can represent the connection or relation between different points. For instance, a 45-degree diagonal line on a Keynesian cross diagram represents points where aggregate expenditure is equal to the level of output in an economy.
In pedigrees, a diagonal line might be used to connect parents to their offspring, indicating the flow of genetic information. In all these uses, the diagonal line serves a different purpose, but it always implies a dynamic relationship, whether that is between artistic elements, mathematical variables, or genetic inheritance.