JWilliam Schopf Examined Australian Sedimentary Rocks That First Formed 3

Multiple Choice

J.William Schopf examined Australian sedimentary rocks that first formed 3.5 billion years ago and observed chains and clumps that resembled modern cyanobacteria.What evidence in the sediments and fossils indicated that these were remains of living organisms?

A) The structures occurred in sediments deposited in water.
B) The ratio of carbon isotopes in them results only from photosynthesis.
C) The structures that were analyzed were microscopic.
D) There was an indication that oxygen had been produced.
E) There was an indication that oxygen had been consumed.