A flash of red light followed by a flash of far-red light given ...

[xclash]

A flash of red light followed by a flash of far-red light given during the middle of the night to a short-day plant will likely
A) cause increased flower production.
B) have no effect upon flowering.
C) inhibit flowering.
D) stimulate flowering.
E) convert florigen to the active form.

[clippers!]

I chose B and got the answer, hope that helps.