I voted for "sometimes I use an alarm clock"...

I tend to wake up fairly early in the morning & just doze until I get up. Therefore it's not that important for me to use an alarm. I would have one set just as a back up if I was working or had some other commitments though.

However, I am using one at the moment anyway just because the mornings are dark & I might be more prone to oversleeping a little. In the summer generally I'll be kept awake by the sunlight in the mornings, so wouldn't have that problem.

I like to get up at the same time every morning regardless of any commitments or not though, so my alarm is always set for 06:50.