The answer is Echinoderms.
According to the Embryological studies, the most ancient chordates were closely related to the ancestors of the echinoderms. Echinoderms are members of the group Phylum Echinodermata of marine animals. Some known echinoderms are starfish, and sea cucumbers.
I believe the correct answer is the second option. Monocots and dicots are two groups of angiosperms. This group of plants are seed bearing plants. Flowers are their reproductive system where the ovules are being enclosed in the ovary. Angiosperms can be found in every habitat from grasslands and forests to deserts and sea margins. Angiospersms are divided to monocots and dicots. Monocot plants are characterized by having one cotyledon while dicots have two. Also, leaf veins of monocots are branched while that of dicots are parallel. The root system of monocots is a fibrous root system while dicots have a taproot system.
The vinegar would tend to diffuse into the agar blocks decreasing the amount of vinegar outside the agar cubes and increasing the volume of agar cubes. Diffusion<span> is the movement of particles (ions or molecules) from an area of higher concentration to an area of lower concentration.
</span>