Abstract: The present application intends to solve the problem of concealing a choice selection from third-party vision using optical effects. Disclosed are methods designed so that the user making the selection can easily tell the difference between the two types of option, correct choice versus confounder, but that difference is blurred rapidly with distance—up to one meter distance becomes indistinguishable. The disclosed methods can be used to make individual choices (2) in environments of proximity with others while maintaining the confidentiality of choice, for example, questionnaires (1) in various fields of education, ATM, voting booths, etc.