Which is a characteristic of pseudoscience?

Pseudoscientific phenomena are "shy" or "fragile" in that they often disappear or weaken noticeably when subjected to well designed experiments, especially with nonbelievers.The ability to identify stimuli that are not visible is sometimes striking when two believers conduct a study; when independent scientists conduct the study, the effect is often attenuated or eliminated.

Pseudo scientific phenomena are shy or fragile

The reactants are co_{2} aka carbon dioxide and h_{2}o aka water along with light energy