1. What sort of tone do you like?
Tone is irrelevant to game design. What it sounds like you are asking is "How detailed do you like your games?" And I like D&D because it has a roughly simple level of detail that grows as large as you want when you start digging deeper into it.
2. How do you feel about the world or setting you play in?
D. but I do care about each. I think D&D includes all these approaches because they aren't setting design features, but player strategies in how they play the game. Anyone can focus on the setting or ignore as they choose.
3. How historically accurate would you like the setting you play in to be?
D. I think D&D doesn't limit itself unless the players elect a limited setting. Anything can be added at any time really.
4. How serious should the game experience be?
D. but again, it matters each time. No game needs to dictate mood to its players. Again, that's personal strategy and up to them.
5. Should continuous boldness be rewarded or punished?
B. Games meant to challenge players are balanced. Games that are weak obviously lack challenge. Games that are death spirals are antagonistic to player growth. You master those games by not playing them. What's great about D&D is that no challenge is uniform, but instead relatively balanced with the players having the ability to seek it or avoid it.
6. How much freedom should the characters have in choosing their adventures?
A. Total, but you mean the players right?
7. Should players be heroes of light in a dark world (or vice versa)?
D. Again, but it matters to each player. They can define good and evil for themselves if they want or look at it as all grey. The great thing about D&D is that it accommodates both at the same table.
8. How much actual role playing do you like in a session?
D. Again. Actual role playing isn't performing a fictional character, but if anyone wants to do that they can.
9. How important is it that players make in-game decisions as a group?
D. Again, but this is one of the most important elements of D&D's game design. At every point in the game each and every player is making the decision on whether to compete with others, cooperate, or go it alone. Even traditionally shared actions (like initiative) don't have to be done as a group. At core, each player is playing their own separate game.
10. Which of the above the above questions is the most important to you?
I guess 5 or 9. There's a lot of false assumptions here about games.