Final answer:
The social worker should first ask the client to describe the content of his thoughts. This will help the social worker gain a better understanding of the client's concerns and identify any patterns in the thoughts. Thought-stopping and thought replacement can be taught as strategies to manage thoughts, but it is important to establish rapport and gather comprehensive information first.
Step-by-step explanation:
The social worker should first ask the client to describe the content of his thoughts (option A). By doing this, the social worker can gain a better understanding of the client's specific concerns and identify any patterns or themes in the intrusive thoughts. This information will help in formulating an appropriate treatment plan.
Once the content of the thoughts is known, the social worker can then proceed to teach the client thought-stopping and thought replacement techniques (option B or C). These techniques can help the client interrupt and replace negative or distressing thoughts with more positive and adaptive ones.
However, it is important for the social worker to establish rapport and gather comprehensive information about the client's experiences before jumping into specific strategies for managing thoughts.