It should be D, cells are parts, tissue is part and organ is part of a system.
Plastic pollution is the correct answer
The one abt respiration the answer is the first one and circulatory system is the last one that says “delivery molecules …”
Answer:
it is easier for them to have an octet of electrons(8e)
Each ion will: obtain the noble gas structure, each atom has high ionization energy
Explanation:
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