Parathyriod glands produce a parathyriod hormone aka PTH
The answer is A: Mass extinction.
"Abrupt disappearance of many land and marine species" = extinction of many species.
Answer: the Earth's spheres interact with other planets in the universe
Explanation: the Earth has different layers and its atmosphere and then when it is in contact with the outer space it can rotate around other planets
Answer:
C. high construction costs
Explanation: