Which of the following correctly shows the internal switching diagram for a drum switch?

The internal switching diagram for a drum switch is typically designed to illustrate how the switch can control the direction of motor rotation or the state of a circuit. In this context, the correct answer indicates that option B accurately represents the layout and connections of the switch's internal mechanisms.

A drum switch usually has multiple terminals that can be connected and disconnected in various configurations to control the flow of electricity. The diagram must show how these terminals interact and lead to the changes in state that are characteristic of a drum switch, such as reversing motor direction or switching between different operational modes.

The representation in option B likely includes the right orientation and configuration of connections that demonstrate how the switch would allow for different paths for electrical current depending on its position. This is crucial for understanding how operators can achieve desired machine operations through mechanical manipulation of the switch.

In contrast, the other options may not accurately reflect the standard arrangement of terminals or the functional logic associated with a drum switch. They may misrepresent the connections or the operational features that enable the effective control mechanisms that define drum switches. Thus, option B is the correct choice as it successfully illustrates the proper internal switching diagram essential for understanding how the switch operates in practical applications.