Question

how do homologous structures show common ancestry? they show similarities between species and which organism first developed the structure. they show us the genetic makeup of extinct organisms. they show the situation that caused a species to branch off from the original.

Explanation:

Homologous structures are anatomical features in different species that have a similar underlying structure, indicating they were inherited from a common ancestor. They show similarities between species, which implies a shared evolutionary origin. The first option correctly describes this concept. The second option is incorrect as homologous structures do not directly show the genetic makeup of extinct organisms. The third option is also incorrect as homologous structures do not show the specific situation that caused a species to branch off.

Answer:

They show similarities between species and which organism first developed the structure.