If I want to invest $1200 in mid-May, what is the best Stock Market to invest those money in and have the most profitable gain if I sell them in Late December?

I was thinking about Apple or Microsoft.
What do you think?

Look at these:

Try ATK:CA

http://www.google.ca/finance?q=atk

Try HLO:CA

http://www.google.ca/finance?q=hlo

Try VER:CA

http://www.google.ca/finance?q=ver

Try SUV:CA

http://www.google.ca/finance?q=suv

I bought them last month and got more than 40% profit. Do you own DD, I’m not recommending any but you want to have "the most profitable gain", you need to do some efforts.

Apple or Mac for 3% in a year!