Answer:
Option A , Convergent Evolution
Step-by-step explanation:
In a convergent evolution, similar characteristics or traits develop in species belonging to different race or ancestry groups.
As in this case , Earthworms are invertebrates while caecilians are amphibians but they both have the ability to burrow, have slender long body and also live in similar habitat (i.e moist soil) . Both the species (i.e earthworm and caecilians) have different origination but they have adopted similar characteristics/traits.
Hence, option A is correct.