Searching for ball - identifying ball
If you hit your ball into thick bush/trees, and play a provisional, when searching for your original ball, if you see a ball in the bush, do you HAVE to identify the ball to see if it might be yours? In some cases, you may see a ball deep in a bush, and know you're way better off playing the provisional. Once you've seen the ball, do you have to try to get in there and identify it? In some cases, it may be near impossible to get to a ball.
On a related note, when searching for balls, are you allowed to ask whoever is helping look for your ball, to only look in places where you'll be able to make a shot. In other words, "don't bother searching under logs or in the deep crap"