Question

common ancestry and structures
new species evolve from a common ancestor. we show this evolution in an evolutionary tree. over time, we look and compare different kinds of structures. vestigial structures are structures that once had a purpose but are no longer needed. homologous structures are structures that are related and shared between species. analogous structures serve the same function but are not the same.
darwin stated that all species have descended from other species with modifications over time. what does this mean?
most life started out in the oceans.
plants and animals have co - evolved.
all life shares a common ancestor.

Explanation:

Darwin's idea of species - descent with modification implies a common origin for all life, from which different species have evolved over time through changes.

Answer:

C. All life shares a common ancestor.