NFHS mistake

[Nevadaref]

NFHS Part 2 question 44:
A personal foul cannot occur during a dead ball.

NFHS Key answer: True 4-19-1

SECTION 19 FOUL
A foul is an infraction of the rules which is charged and is penalized.
ART. 1 . . . A personal foul is a player foul which involves illegal contact with an opponent while the ball is live, which hinders an opponent from performing normal defensive and offensive movements. A personal foul also includes contact by or on an airborne shooter when the ball is dead.
NOTE: Contact after the ball has become dead is ignored unless it is ruled intentional or flagrant or is committed by or on an airborne shooter.