In the context of the formation of Petroleum which of the following statements are true?

(A) Petroleum is produced from the organisms living in the sea.

(B) Dead bodies of organisms living in the sea get deposited at the bottom of the sea and get covered with layers of sand and clay.

(C) Over millions of years, absence of air, low temperature and low pressure transformed the dead organisms into petroleum and natural gas.

(D) Over millions of years, absence of air, high temperature and high pressure transformed the dead organisms into petroleum and natural gas.