Explanation:

When a process is rolled back as a result of a deadlock, the difficulty that arises is starvation. Starvation occurs when a process is unable to proceed or complete its execution due to resource unavailability or resource allocation issues.

Here is a detailed explanation of why starvation is the difficulty that arises when a process is rolled back as a result of a deadlock:

1. Deadlock:
- A deadlock is a situation where two or more processes are unable to proceed because each is waiting for the other to release a resource.
- Deadlocks typically occur when processes acquire resources in a specific order and hold them indefinitely.

2. Rollback:
- Rollback is a mechanism used to resolve deadlocks by reverting the system to a previous stable state.
- When a process is rolled back, it means that its state is reverted to a previous checkpoint, and any progress made by the process after that checkpoint is discarded.

3. Starvation:
- Starvation refers to a situation where a process is unable to proceed or complete its execution due to resource unavailability.
- In the context of a deadlock, when a process is rolled back, it loses any progress it has made in acquiring resources.
- If the resources that the process requires are still being held by other processes involved in the deadlock, the rolled-back process may not be able to acquire those resources again.
- As a result, the rolled-back process may continue to be unable to proceed or complete its execution, leading to starvation.

Conclusion:
When a process is rolled back as a result of a deadlock, the difficulty that arises is starvation. The rolled-back process may be unable to acquire the necessary resources again, resulting in an inability to proceed or complete its execution.