In short day plants, flowering is induced by
(a) photoperiod less than 12 hours
(b) photoperiod below a critical length and
uninterrupted long night
(c) long night
(d) short photoperiod and interrupted long night
(a) photoperiod less than 12 hours
(b) photoperiod below a critical length and
uninterrupted long night
(c) long night
(d) short photoperiod and interrupted long night