Denmarks strategy for sustainable development should therefore also be seen as the countrys response to the challenge of Agenda 21 which was adopted at the UN General Assembly in Rio in 1992 to prepare national strategies for sustainable development

Can you repeat this sentence, but add in punctuation?
Denmark's strategy for sustainable development should therefore also be seen as the country's response to the challenge of Agenda 21, which was adopted at the UN General Assembly in Rio in 1992, to prepare national strategies for sustainable development.