The United Nations was founded in 1945. It aims to solve global issues such as climate change and civil war.

• A. The United Nations was founded in 1945 when it aims to solve global issues such as climate change and civil war.
• B. The United Nations was founded in 1945, so it aims to solve global issues such as climate change and civil war.
• C. The United Nations, which was founded in 1945, aims to solve global issues such as climate change and civil war.
• D. The United Nations aims to solve global issues such as climate change and civil war which was founded in 1945.