Answer:
space
Step-by-step explanation:
The limiting factor that the illustration closely relates to in the environment is space.
Limiting factors are environmental factors that hinder the population of living organisms living in that environment from reaching their maximum reproductive capacity, also known as biotic potential. Limiting factor include space, foods and other environmental resources such as sunlight, nutrients, etc.
In the illustration, the cupcake tray can only hold 24 cupcakes while Ethan has batter for 25 cupcake. The tray thus is limited in space and as a result, one cupcake batter is left floating. The has limited the production capacity of the cupcake batter.