Answer:
scientific theory is the answer
The answer would be: <u>Molten material that cooled quickly.</u>
Igneous rocks are formed by the cooling of molten material. So we can cross out the last two choices. The rock has no identifiable crystals so it is most likely an Extrusive igneous rock. They form on the surface where they cool quickly.
Those that form underground are called intrusive rocks. They cool slowly allowing enough time for crystal formation.
Characteristics of Lancelets:
Small
Elongated
Marine invertebrate
Lacks a jaw
No sense organs
Has a notochord
Example: Lamprey
Characteristics of Tunicates:
Marine invertebrate
Has an outer coat that is rubbery or hard
Has two siphons
Examples: sea squirts, salps
I hope this is the answer that you were looking for.
In order:
kingdom, phylum/division, class, order, genus, species
This might represent evolution of a species or the influence of the environment on the expression of a genotype.