Cephalization, the clustering of neurons and interneurons in the anterior part of the animal, is apparent in cephalization, the clustering of neurons and interneurons in the anterior part of the animal, is apparent in hydra. sea stars. cnidarians. planaria.

Planaria.

Explanation:

The kingdom eukarys is divided into the different phyla including almost all the animals. The organism are classified on the basis of their level organisation, cavity and on the basis of coelom.

The cephalization is initial process for the deposition of nervous tissue in brain. The cephalization is absent in porifera and coelenterate.  The planaria also known as flat worms shows the process of cephalization and this process becomes more complex in higher animals.

Thus, the correct answer is option (4).

genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).

evidence and logical support is essential for a scientist to do in order to maintain credibility. this is because no one can believe without any logic and without any evidence.hence a scientist can maintain credibility by proving himself and by answering logically so experiments prove very beneficial. logical hypothesis give conclusion which is acceptable. therefore, there are two main factors to maintain credibility by a scientist is evidence and logical support.