Just passing by as a seasoned sheep owner...
1) As someone said: Don't fly over their heads. They will be scared and run all over the place.
2) Try to land in a corner of the pasture, this will provide the sheep (or goats!) with more options to run around/away.
3) If there is no corner; seek out a place with very few sheep. (Yes, I couldn't resist... ;-D )
4) When you have landed, don't leave your machine unattended. I vouch for sheep (and goat) curiousity and if that machine is unattended you might very well have sheep aviation school going on when you return.
5) Sheep are often very friendly once they have sniffed you on your cheek (they don't go for the crotch like dogs..) and usually love a nice petting.
6) Never feed bread or the like to sheep and goats.
So...
A - YES!! (It can be a lot of fun watching them but please remember that they can literally die if they get too scared... farmer wanting money for dead sheep... local news... you see where I'm going...)
B - no
C - no
D - no