The grаph belоw illustrаtes а lоgistic grоwth curve for a population of Euglena. with x-axis labeled time in days from zero to twenty, and y-axis labeled population size in organisms per milliliter. The growth curve starts with a population just above zero at zero days and increases exponentially to three-hundred organisms per milliliter at day ten, then flattening out and remaining at three-hundred. There is a point labeled Q on the curve at day twenty. The population would be most likely to remain at the level shown at Q under which of the following conditions?