Which Of Van Goghs Sunflower Painting Is The Best I Need Ur Help To Answer A Few Questions On Vincent Van Goghs Painting - Sunflowers?

I need ur help to answer a few questions on Vincent van goghs painting - Sunflowers? - which of van goghs sunflower painting is the best

What is the style, period or movement of this work was it?
What materials, lines, shapes and colors used by the artist?
Why do you think the artist colors, lines and shapes?

Tell me think, what u.