Howard Taped Pictures of Rainbows All Around the Room as Visual

Howard taped pictures of rainbows all around the room as visual aids for his speech.He never referred to the pictures but simply created an atmosphere for his presentation.Was this an effective use of visual aids,according to textbook guidelines?

A) Yes;the pictures created the kind of mood the speaker wanted.
B) Yes;but only because they were large enough for the audience to see.
C) No;because you should explain your visual aids,not just show them.
D) No;because there were too many of them to create any kind of effect.