Amount of rainfall
I’m not sure if this is right but I think it is because all of the rest are major parts of ecosystems, and although rainfall is too, it’s more of a natural source that happens anywhere whereas the rest of the options may determine the ecosystem
Strawberries and oranges are high in Vitamin C (in fact, a cup of strawberries has more Vitamin C than a medium-sized orange) as well as potassium. We can thus infer that Layla is probably deficient in these nutrients. To supplement Layla's intake of Vitamin C, Ruby can serve red and green peppers and kiwi, which (like strawberries) have more Vitamin C than an orange. To supplement Layla's potassium intake, Ruby can serve spinach, broccoli, and cantaloupe.
The largest elliptical galaxies can be over a million light-years in diameter. The smallest "dwarf elliptical" galaxies are less than one-tenth the size of the Milky Way! Elliptical galaxies have very little gas and dust. Since stars form from gas, little star formation occurs in elliptical galaxies.
