Given a scientific passage and an answer, generate a question for the given answer.

[EX Q]: Passage: Solutions can also become supersaturated , where the amount of solute dissolved exceeds its solubility. Supersaturation most commonly occurs when a saturated solution is slowly cooled. They occur frequently in geological and meteorological processes. Supersaturated systems are unstable, and eventually, the solute will precipitate until a saturated solution is regenerated. We can quantify supersaturation by looking at solubility curves. If the ratio of solute to solvent is above the saturation curve at the given temperature, the solution is supersaturated. If it is on the curve, the solution is saturated, and if it is below the curve, the solution is unsaturated. Answer: its solubility
[EX A]: Solutions can also become supersaturated , where the amount of solute dissolved exceeds what?

[EX Q]: Passage: Vascular tissue runs through the ground tissue inside a plant. It transports fluids throughout the plant. Vascular tissue actually consists of two types of tissues, called xylem and phloem. The two types of vascular tissue are packaged together in bundles. You can see them in the celery in Figure below . Answer: xylem and phloem
[EX A]: What are the two types of vascular tissues?

[EX Q]: Passage: Competitive Exclusion Principle Resources are often limited within a habitat and multiple species may compete to obtain them. All species have an ecological niche in the ecosystem, which describes how they acquire the resources they need and how they interact with other species in the community. The competitive exclusion principle states that two species cannot occupy the same niche in a habitat. In other words, different species cannot coexist in a community if they are competing for all the same resources. An example of this principle is shown in Figure 45.24, with two protozoan species, Paramecium aurelia and Paramecium caudatum. When grown individually in the laboratory, they both thrive. But when they are placed together in the same test tube (habitat), P. aurelia outcompetes P. caudatum for food, leading to the latter's eventual extinction. Answer: competitive exclusion
[EX A]:
Which principle states that two species cannot occupy the same niche in a habitat?