During carbinferous period, what were largely responsible for regulating climate on land masses?

Drastic boundary changes can occur for all of the following reasons except for a. a shift in the way a river flows b. the collapse of a government system c. a conflict between two neighboring groups d. one country's decision to sell land to another country select the best answer from the choices provide

Which area on the map would be most likely to have the most oil exploration in since the start of the 21st century? a) b) c) d) plz me

Ozone in the upper atmosphere has been depleted by a. sulfur dioxide. b. chlorofluorocarbons. c. carbon dioxide. d. oxygen.