You could give any answer to those kind of questions and as long as you seem confident and sound truthful, you breeze past and aren't given a second look. The C

You could give any answer to those kind of questions and as long as you seem confident and sound truthful, you breeze past and aren't given a second look. The CBP officer might just happen to be knowledgeable in your field enough to be able to verify your answer or he may have no clue and just pulled a question from his ass. They are just looking for a reaction and the tone of your answer.