Would this years december be considered as 2018 or 2019?

2019 starts in the next January. December would still be in 2018.

Ithink the answer to that would be b):

Humans have survived and thrived in mexico city by using technology to create greater access to land. when the spanish conquered the aztec capital, tenochtitlan, in the 16th century, they built mexico city by draining the lakes and filling in the lake water to create more arable land for agriculture. this technique of land reclamation has continued to be fundamental to human civilization in mexico city.