A Gardener in Canada Wants to Surprise His Mother on Her

A gardener in Canada wants to surprise his mother on her birthday and make her favorite Shrubalthea bush flower in May instead of the end of June.The bush is growing in the greenhouse.Which of the following might make the Shrubalthea bush flower early?

A) fertilizing the bush
B) grafting leaves of a Shrubalthea that was exposed to long nights
C) grafting leaves of a Shrubalthea that was exposed to short nights
D) exposing flower buds of the Shrubalthea bush to long nights
E) exposing flower buds of the Shrubalthea bush to short nights