I don't know your options, but there is one clear cause and effect relationship between the two:
As the agricultural methods advanced, people were more productive creating food. This means that not everyone had to engage in farming! And this allowed specialization for other jobs, just as smiths, which typically live in the cities.
The Cape Verde Islands are included in the coastal West African nations.
The correct answer is b. Cape Verde.
Hope that helps~
Fundamental principle is the answer to the question
Greenhouse emissions of tar sand, per barrel, are more than conventional crude oil. This is because, it takes more energy to extract the bitumen from the tar sand and more so, to convert the bitumen to usable oil taking up even more energy. This energy is usually derived from burning natural gas. Emissions by tar sand are approximately 100 kg CO2 per barrel while conventional oil is approximately 30 kg CO2 per barrel.