In Earth's Solar System,a Nebula Is Believed to Have Formed

question 84

Multiple Choice

In Earth's solar system,a nebula is believed to have formed around the early Sun.Planetesimals gradually coalesced out of this nebula and accreted to form the planets-a process requiring a total of about 100 million years.How would you describe the Sun at the end of this process?

• A) The Sun was about halfway through its protostar phase.
• B) The Sun had just become a pre-main-sequence star.
• C) The Sun was at the end of its existence as a pre-main-sequence star.
• D) The Sun had ended its pre-main-sequence phase and had become a main-sequence star.

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Definitions:

Polyphyletic

A group of organisms derived from more than one common evolutionary ancestor or ancestral group, indicating they do not share a common lineage.

Phylogenetic Trees

Diagrams that represent the evolutionary relationships among various biological species or other entities, based upon similarities and differences in their physical or genetic characteristics.

Systematists

Systematists are scientists who study the classification and evolutionary relationships among organisms, organizing them into systems of taxonomy.

Evolutionary Relationships

Descriptions of how different species are connected to each other through common ancestors, detailing the path of divergence and speciation.