Which of the following does an IBD convey?

The correct choice highlights that an Internal Block Diagram (IBD) conveys the structure of a single block and its internal services. An IBD is used in systems modeling to represent the internal components, parts, or relationships of a block, showcasing how these components interact and are organized within that block.

In this context, the IBD allows modelers to express clearly the connections between the internal parts and the interfaces they provide, focusing on how these elements work together to fulfill the block's functionality. This is crucial for understanding the design of complex systems, as it provides insight into how each part of the block contributes to the overall functionality.

While it is true that IBDs can provide insights into system architecture and interactions, that specificity about a single block and its services distinguishes this choice as the most accurate. The representation of behavior during execution is typically captured in other types of diagrams, like sequence diagrams or activity diagrams, rather than an IBD, which focuses more on structure than dynamic behavior.