if the burden seems too much to bear remember the end will justify the pain it took to get us there

So, nice cliffhanger there, right? I'll tell you the rest now. So after he asked me, my face turned flaming red and I didn't know what to say. What I was thinking was something like this "holy crap, what do I say, my parents would never go for that, I don't think I would go for that, I know he smokes, he probably parties a lot considering he's friends with Jared, and he'd probably get drunk at the concert and try to rape me in a dark alley or something, I don't know him at all, I've only talked to him twice, and I like someone else." At the same time I was flattered that he asked me out, just because that's a natural thing, to be happy if someone's interested in you. But I don't want to get involved with someone that old. But I had no clue what to say so I told him I'd think about it. He was like, "What's to think about? It's a concert." And I said something brainy, like "Ummm, I don't know...." What I really meant was "I'll think about what my excuse should be." So I have work tonight and he might come in, so what do I say?
a) the absolute truth, which would be something like: "My parents would never let me go on a date with someone your age; I don't particularly want to go on a date with someone your age; I don't know you very well and if I got to know you better I probably wouldn't like you very much; I don't like Linkin Park that much; and I like someone else."
b) a half-truth: "I kinda sorta maybe am in the process of getting a boyfriend."
c) a flat out excuse: "I think I'm going to be on vacation on July 24." Cuz I might be!
d) some variation on these.
I'm leaning towards choice c. Easy enough, and it wouldn't be a lie. I know I'm going to Laura's house sometime this summer, and hopefully Katies. That'll be the week after I get back from Australia, so it's highly possible that I'll be at Laura's then, even though we haven't figured it out yet. So I could tell him that and if he ever asks me again I'll just tell him I have a boyfriend or something, who know's maybe I will by that time...eesh. It's just a weird situation. ANY ADVICE WOULD BE GREATLY APPRECIATED!!! By 5 o clock tonight...just pick one, a,b,c, or do and leave a comment. Or think of some other excuse for me. Holy junk. Weirdness.
On a side note: SAT tomorrow!!!! And I think I'm getting sick. Yuck.