White on white definately a tough challenge to avoid the over exposured areas which cause your subject to blend in with the background and that is what happened with two of the three drops here.
This appears to be slightly out of focus and just needs a little less softness to it.
Your composition is good and your use of thirds is well excuted. As for meeting the challenge. Yes without any question you met it.
Interesting pictue. Love the trail on the one in front right. Its seems a bit soft or out of focus which makes it almost melt into the background. The frame makes it work though. Good job!