none of the above.
speed is something that is genetic and there is very very little room to get faster beyond your genetic limit even with gear(which does nothing for speed). and that little room to get faster requires very very intense speed training that will only make you
slightly faster. steroids do not get you faster, speed training does. constantly working your fast twitch muscles(which are only activated by sprinting).
trust me, I played football all the way up till College, I went to a speed training center called Athletic Republic for 8 years. Speed training is by far the most intense exercise I have ever been a part off.
Here's a clip from AR, doing stuff like this gets you faster:
https://www.youtube.com/watch?v=OgovRZrJb4U
The common belief that gear makes you faster is nothing more than a myth. It's something that sounds true on paper. That is why all those Russian Olympians in the 80's tested positive for it.
I obsessed like hell for 8 years on how to get faster because it was the #1 thing on the field holding me back. I busted my ass really hard from waking up at 5am to go hit the school bleachers for 45 min every morning. To plyo workouts with coaches during the day. Speed training facility at night. 8 years later I went from a 4.78 forty yard time to a 4.69
And I took gear in College. Did not do a thing to my speed.