B? Human population are sometimes concentrated in areas that are lacking resources
Hydrogen is used by plants which combine it with carbon during the photosynthesis process and release oxygen into the atmosphere which is used by all living beings.
Answer:
In a <u>u</u><u>n</u><u>i</u><u>t</u><u>a</u><u>r</u><u>y</u> state, smaller member states agree to participate in forming a larger state.
<span>B. agricultural production. :)</span>