D. Oxygen
It refers to the pathway by which a chemical element is moved through both the abiotic and biotic compartment of an ecosystem.
You didn't put any answer choices, but air and water are generally the greatest.
Answer:
1. Klinefelter syndrome
2. Nobody can be born with a single X chromosome
Explanation:
1. A genetic condition in which a male is born with an extra copy of the X chromosome
Klinefelter's syndrome isn't inherited, but rather occurs only as a result of a random genetic error after conception.
Males born with Klinefelter's syndrome may have low testosterone and reduced muscle mass, facial hair and body hair. Most males with this condition produce little or no sperm,
2. Sex chromosome occurs due to combination of the X and Y chromosome of both parents.
C. Cells
Cells make up organs, which make up organisms, which make up populations
