The International Astronomical Union (IAU) defines a constellation by its: boundary

star pattern

brightest star

Greek name

Each constellation is a region of the sky, bordered by arcs of right ascension and declination. ... Together they cover the entire celestial sphere, with their boundaries adopted officially by the International Astronomical Union in 1928 and published in 1930.

So I would say its A : Boundary

Explanation:

- Eijiro <3

Love the pfp by the way! :D

i think its A but im not sure

Explanation:

step 1 ammonium can be absorbed by plants, but some is converted into nitrates which are better for plants to absorb. this is called nitrification. 2. step 2 the deer eats the plants and uses the nitrogen-containing proteins for cell growth. 3. step 3 bacteria in the soil conduct nitrogen fixation to convert nitrogen gas from the atmosphere into ammonium. 4. step 4 some of the nitrates are absorbed back into plants, but denitrification breaks down the nitrates into nitrogen gas released back into the atmosphere. 5. step 5 nitrogen is found in the urine, which gets broken down into ammonium through the process of ammonification. 6. step 6 plants absorb the ammonium and begin assimilation, the process to add the nitrogen to protein.

the supermassive black hole is in the middle of the galaxy.