The correct answer is B. Young.
Juvenile means young or immature. It can also refer to something that is characteristic of young people, such as a juvenile delinquent.
Hidden means not seen or not easily found. It can also refer to something that is kept secret or concealed.
Humorous means causing laughter or amusement. It can also refer to something that is funny or comical.
Tedious means boring or tiresome. It can also refer to something that is long and drawn-out.
In this case, the correct answer is B. Young because juvenile means young or immature. The other options are incorrect because they do not have the same meaning as juvenile.