▶ Less than 15 minutes/day
( )
▶ 15 minutes to less than 30 minutes/day
( )
▶ 30 minutes to less than 1 h/day
( )
▶ 1 h to less than 2 h/day
( )
▶ 2 h to less than 4 h/day
( )
▶ 4 or more hours/day
( )