I had to look for the options and here is my answer:
Based on the attached details about the cattle egrets, how an ecologist would explain this expansion is that, a habitat that has been not been occupied by the egrets and the native herons acquired the biotic and abiotic standards <span>of the cattle egret transplants and their descendants. (This is based on the actual option attached to this question.)</span>
Cnidarians uses arm-like parts called <u>tentacles</u> to sting.
Explanation:
Animals belonging to genus Cnidaria use arm-like structures called tentacles to sting. The cnidarians tentacles are present with specialized stinging cells called cnidocytes.
These cnidocytes are responsible for the stinging action which is done by the cnidocyte organelle called the nematocysts or the stingers.
Nemotocyts contain coiled thread or barb-like or hair-like structures which fires the toxin out while stinging.
The opening or the mouth-like parts on the tentacles contain numerous cnidocytes which releases toxin when the tentacles are touched by another organism or when the cnindarian touches its prey.
Amino Acids. Proteins are the most diverse biomolecules on Earth, performing many functions required for life. Protein enzymes are biological catalysts, maintaining life by regulating where and when cellular reactions occur. Structural proteins provide internal and external support to protect and maintain cell shape.
Hope this helps :)