Server
 

After R1 beckons for serve, server S1 attempts to bounce the ball on the floor. The ball hits her foot and rolls away.

Should R1:
a) blow the whistle and reset (i.e, replay, not re-serve)
b) blow the whistle and signal re-serve
c) count (slowly) to 5 and then whistle a fault (unless S1 can retrieve the ball and either serve or toss the ball and not serve)
d) other

I say "b". My reading of the rules say that the R1 should allow a re-serve. 8-1-6.

Re-Serve
 

In this situation, there was no attempt to play the ball, therefore, it is a re-serve. (NFHS 8-1-6)

zoz

8-1-6 "A re-serve shall be called when the server releases the ball for service, then catches it or it drops to the floor.

That bold part didn't happen in the OP.

Not saying hat it shouldn't be a re-serve, only that making it so requires (for me) some additional explanation / interpretation

Doesn't this depend on the level of play and the official's discretion since "the service" never began? The officials can stop the match for any reason.

I suppose that if a player dropped the ball, it crossed the line without touching the foot, I'd likely call for a replay and not a reserve.

However, it would be interesting if the servers teammate picked up the ball, tossed it back to them, and it was served within five seconds, or if the player crossed the end line, retrieved the ball, and returned to the service area for a legal serve, all within five seconds...whew,
It seems like a nightmare that is avoided by stopping and permitting a replay or reserve.

Option C seems like I'd be breaking into jail.

Correct. By rule, C is the correct answer. There has been no toss for serve, so no justification for a re-serve.

Now, if you're working some lower level ball, you could probably get away with killing the play and starting over, but in a heated match, C is the way to go. Maybe make sure they can see that they are on a (slow) count, but if they aren't even looking at you...lesson learned.

This is incorrect. Correct application of the rule is "C"