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Which of these would be evidence that cyanobacteria evolved the ability to perform photosynthesis on earth over 2 billion years ago? A) A decrease in glucose in cellular fossils more recent than 2 billion years ago B) An increase in oxygen gas in the atmosphere and oceans starting 2 billion years ago C) An increase in carbon dioxide levels in the atmosphere and soils from 2 billion years ago D) The presence of eukaryotic cellular structures trapped in ice from earlier than 2 billion years ago