Explain the role of the D principle in SOLID principles and its significance for software development.

The Dependency Inversion Principle (D) in SOLID states that:

• High-level modules should not depend on low-level modules. Both should depend on abstractions.
• Abstractions should not depend on details. Details should depend on abstractions.

This helps create flexible and easily extendable systems, where changes in low-level components do not lead to changes in high-level logic. For example, instead of direct dependence on a specific database implementation, a class works with a repository interface. This simplifies testing and replacing components without changing client code.