Life on Earth Is Believed to Have Begun

Multiple Choice

Life on Earth is believed to have begun

A) where only pure liquid water existed
B) where only the element carbon existed
C) Choices"a" and "b" are both wrong! Both liquid water and the element carbon appear to be crucial for life
D) Choices"a" and "b" are both wrong! Both liquid water and the element carbon are totally unimportant in life as we know it.