Answer:
I believe the answer is A.
<em>I apologize if I'm incorrect, please let me know if I am tough I'm pretty sure I'm right.</em>
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Let us look at the what, why and how of studying extreme places like the deep earth and the deep space. Scientists need to figure out as to 'what' they want to look at such places, be it a new exotic creature or bio-genesis (birth of life). Unless there are several testable hypothesis constructed, such a study cannot begin. The 'why' aspect deals with the purpose of such research and expeditions. Is it of any use to the humans, or will it improve our current understanding of a phenomenon? The 'how' aspect deals with the technology and the economic assistance that can help in undertaking such a research. All these are the challenges that needed to be thoroughly considered to make such a research or expedition possible.
Gasse you cant see and liquid you can see or toch and feel them
hope that helps
I believe you're looking for "invasive species"
A.) Multicellular <span>organisms are made up of many different groups of specialized cells
Hope this helps!</span>
