You are building tests using the classification tree below.

Pairwise testing is a technique that reduces the number of test cases by testing only pairs of values for each data item, instead of testing all possible combinations. Pairwise testing is based on the assumption that most defects are caused by interactions of at most two factors. Pairwise testing can be applied to this problem using the classification tree, which shows the data items and their values. By using pairwise testing, the number of test cases will be lower than exhaustive testing, which would require testing every combination of values for each data item. References =

ISTQB Certified Tester Advanced Level Syllabus Technical Test Analyst1, page 2

Data Combination Test (DCoT) | TMap2, section “Coverage level”

Pairwise Software Testing - GeeksforGeeks3, section “Introduction”