You Manage a Greenhouse That Produces Roses for Valentine's Day

You manage a greenhouse that produces roses for Valentine's Day.Roses normally bloom in June.You need to produce roses that bloom in February.After setting the correct photoperiod in your greenhouse, you still do not have blooming roses.Which condition might have contributed to the problem?

A) The heating system allowed for fluctuations in temperature between 20°C and 25°C.
B) The furnace mechanic accidentally turned off the lights for an hour two days in a row.
C) The cleaning crew turned the lights on for an hour three nights in a row.
D) The watering schedule was interrupted for two days in a row.
E) The lights are not strong enough to induce flowering.