Although discussions about environmental issues, including pollution, were prominent in the 1970s, the specific focus on greenhouse gas emissions and climate policies did not gain substantial international traction until the late 1980s and early 1990s.

D is correct. Global temperatures rose significantly even before the 80's so A cannot be correct as others comment here

A is accurate, D is not

A: But in the 1980s, global mean annual temperatures started to rise significantly, and scientific con-sensus around the strong human influence on climate solidi-fied, leading to the formation of the Intergovernmental Panel on Climate Change (IPCC) in 1988 D: There have been various attempts since the 1990s to agree on international climate policies, mainly regarding emissions reductions, at a global level. The first global agreement on climate change was the formation of the United Nations Framework Convention on Climate Change (UNFCCC) in 1992; the first accord on emissions reductions was the Kyoto Protocol of 1997;