Probably B) strenuous exercise. If not B then it's probably A. I don't know for sure though
Part 1: The eclipse observed was a lunar eclipse. The sun is usually not visible during these eclipses. The moon is new during a solar, but full during a lunar. It is red during a lunar eclipse due to a reflection of the Suns light behind earth. It happens more often because Earths shadow is larger than the moons. The umbra is larger as well, so it lasts longer than a solar eclipse.
Part 2: The moon is in the full moon phase. The Earth is in between the Moon and the Sun. The umbra of Earths shadow is cast directly on the moon, casting out the suns light. A tint of the reddish color shines around earth from the Sun making the dark moon appear red. The moons axis is slightly tilted , so the umbra does not hit the moon every month. But when it does? It creates a lunar eclipse.
I would say energy myself, and this is because energy plays a key role in all of these. With trophic levels energy is being transferred amongst the levels. Food chain's is a map of how the energy is passed along the chain. Food web is a web of how energy is transferred, and this is why I would say energy is a keyword.
The Hardy-Weinberg equation is:
where p generally represents the frequency of the homozygous dominant population.
The q usually represents the frequency of the homozygous recessive population, and the 2pq term represents the frequency of the heterozygous population.
