The building of canals was important because it

ANSWER:

The Panama Canal is necessary because it connected the Pacific and the Atlantic  Ocean

EXPLANATION:

It opened up trade between the Atlantic and Pacific oceans. In the old days, Alfred  Thayer Mahan thought that a strong navy meant a great country. So we would need two  navies, one for the Atlantic and one for the Pacific. However, the canal presented it possible to lack only one Navy.

are there any options you can choose from? ?

it is very hard for the climatologists to precisely predict how will the global temperatures be changing so there's lots of models, some of which differ significantly, this is due to multiple factors, and probably the most important is the human activity.

humans have been a key factor in climate change around the globe since the start of the industrial revolution, and in the past few decades the consequences are becoming more obvious. there's lots of emission of pollutants in the atmosphere as well as changing the environment on the surface itself, so it's really hard to predict how will that go in the future because there's some countries that are reducing the damage and are going towards green energy, while others are stubbornly continuing with pollution and damages to the environment.