Diatoms contain chloroplasts that have four membranes. These four membranes are evidence of secondary endosymbiosis (Option c).
<h3>What is secondary endosymbiosis?</h3>
Secondary endosymbiosis is a hypothesis used to explain why diatom chloroplasts have four membranes.
According to this hypothesis, diatoms received different genes from distinct photosynthetic and non-photosynthetic ancestors.
The acquisition of genes of different ancestors led to diatoms having chloroplasts with four membranes.
Learn more about the endosymbiosis hypothesis here:
brainly.com/question/2957447
This character trait is known as homoplasy. the definition of homoplasy that two or more species share a character, but they did not descend from a common ancestor.
This trait is known as convergent evolution, or convergence.
Carbon would build up in the atmosphere.
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