It costs $1,000 to enter the following game of chance, which is based on the outcome of a coin toss (fair coin). If the coin comes up 'heads' then you win and walk away with $1,100, which is a 10% rate of return. If the coin comes up 'tails', then you lose and walk away with $900, which is a -10% rate of return. What is the variance of the returns?

a.0.05 b.0.1 c.0.09 d.0.01 e.0.5