No mention of a penalty, although they do give the source citation for the law.
Since you’re on FR, I can GUARANTEE the fedgov knows far more about you than this document requests....
What specific questions are asked on the 2015 National Content Test?
For each household, we will ask how many people live in the house, and for each person we will ask the name, sex, age, relationship, and race/origin. We also will ask whether the housing unit is owned or rented, the telephone number, and an email address. Some people will receive different versions of question wording because studying the effectiveness of different content is a part of the test.