When a predator feeding on certain prey is removed from the environment, which variable will most likely determine whether or not the prey will survive?

Available food

Explanation:

From the given example, it is called the available food

Predators searches for  a prey to eat, but first it's sit and wait for it. and when a prey is located, the predator thinks whether to attack and kill it.

Once a predator has been removed from that environment, the prey itself whether of lower class animal or different classes of animals becomes available and vulnerable to other higher class of animals who are in search of food for survival.

paper covers rock.

explanation:

rock only smashes scissors.