The answer would be letter C
Answer:asteroid,planet,star,nebula,galaxy, and universe
Explanation:I’m not actually sure im just smart
The answer is A because the heart pumps blood from the heart through pulmonary artery that is low in oxygen and high in carbon dioxide concentration, to the lungs.
The most common elements present in organic compounds are carbon, hydrogen, oxygen, and nitrogen.
1) Are they reliable?
2) Are they relevant?
3) Are they recent?
4) Are they sound resources?
5) Are they a primary source?
6) Are they a secondary source?