A single client, single agency or single community can all be used as a single subject design for a social work tool.
<h3>What is a social work tool?</h3>
These are tools that enhance engagement in the social services so as to hace a more productive interactions between social service practitioners and the people they work with.
Example of a social work tool includes communication, organizational skills, boundaries, code of ethics, persuasion, coordination etc
Therefore, the Option D is correct.
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3rd answer........................
Answer: Al-qaeda was responsible for the tragic September 11 attacks.
Explanation: Al-qaeda took refuge in Taliban. This caused the United States to declare war on Taliban. Later U.S troops were pulled out by United States president Joe Biden.