Again, to be clear, I don't think this is a fundamentally scientific question.
If you show a philosopher how a rose activates the retina and sends signals to the brain, you'll get a response like, "sure, but when I say the subjective experience of a rose, I mean what the mind does when it experiences a rose"...
If you show a philosopher the retinal signals activate the optical processing capabilities of the brain, you'll get "sure, but when I say the subjective experience of a rose, I mean what the mind does when it experiences a rose"...
If you show a philosopher how the appearance of a rose consistently activates certain clusters of neurons and glial cells that are always activated when someone sees a rose, you'll get a response "sure, but when I say the subjective experience of a rose, I mean what the mind does when it experiences a rose"...
Show the philosopher that the same region of the brain is excited when the person smells a rose or reads the word "rose", and they'll say, "sure, but when I say the subjective experience of a rose, I mean what the mind does when it experiences a rose"...
To the philosopher, they have posed a question about "what it's like to experience a rose", and I suggest that NO answer will satisfy them, because they're not really asking a scientific question. They're looking for, as the SEP puts it, an "intuitively satisfying way how phenomenal or 'what it's like' consciousness might arise from physical or neural processes in the brain". But, science isn't under any obligation to provide an inituitive, easy-to-understand answer. The assemblage of brain & nerve functions that are fired when a living being experiences a phenomenon are the answer.