Question

read the excerpt from \climate change an overview\ by the early twentieth century, carbon emissions from fossil - fuel burning reached 1 billion tons a year. automobiles, airplanes, and domestic and agricultural energy demands all contributed to the rising trend. in the 1950s, scientists used a new generation of equipment to confirm that carbon - dioxide concentrations were doubling and that this would have the effect of increased temperatures this excerpt primarily describes the long - term effect of increasing carbon emissions long - term effect of decreasing temperatures short - term effect of decreasing the use of new technology short - term effect of increasing energy demands

Explanation:

The excerpt talks about carbon emissions from the early twentieth century (long - term time frame) and how they were increasing (from fossil - fuel burning, automobiles, etc.). It also mentions that in the 1950s, scientists confirmed that carbon - dioxide concentrations were doubling (a result of the long - term increase in carbon emissions) and that this would lead to increased temperatures (a long - term effect of the increasing carbon emissions). There is no mention of decreasing temperatures (so the second option is wrong). There is no mention of a decrease in new technology use (so the third option is wrong). While energy demands are mentioned, the focus is on the long - term aspect (from early twentieth century to 1950s) rather than a short - term effect (so the fourth option is wrong).

Answer:

long - term effect of increasing carbon emissions