Answer:
True. Yes, the theory can be falsified.
Step-by-step explanation:
Theory X would more specifically refer to the theory of supply and demand, which states that individuals will buy more of a particular good if their income rises. From this theory, comes the concept of "normal good", which are precisely the goods that people buy more as their income rises.
This theory could be falsified by empirical observation: a study could be made, including a good number of subjects, to see whether their purchasing habits are directly related to their income.