Final answer:
Average global temperatures are usually warmer and are expected to rise by 2100, with land warming more rapidly than oceans. The Arctic may see larger increases and even small changes can have significant climatic and sea level effects. Hence, the correct answer is option A.
Step-by-step explanation:
Average global temperatures are usually considered to be warmer rather than cooler. Scientific evidence suggests that by 2100, the global average temperature is expected to increase significantly, possibly by as much as 2°F to 11.5°F, depending on future greenhouse gas emissions. It is also expected that ground-level air temperatures will continue to warm more rapidly over land than oceans. Moreover, certain regions, such as the Arctic, may experience temperature increases greater than the global average due to factors that are not entirely understood yet.
The impact of a 2 or 3°C rise in temperature may seem minimal; however, it is essential to note that the average global temperature during ice ages was only about 6°C lower than today. A few degrees of change can lead to significant alterations in sea level and climate conditions.