Based on the tax system specification as described below, using boundary value analysis, which would be the best test set to explicitly test on single boundary value fully?
Tax system
A tax system needs to be updated due to new legislation. For a person with a salary of less than € 20 000 and who is married, the tax needs to be recalculated.
If a person has at least three and less than six children, an additional 10% reduction is applicable.