You use a line best fit for a set of data to make a prediction about an unknown value. The correlation coefficient for your data set is -0.993. How confident can you be that your predicted value will be reasonably close to the actual value?

a. I can't be confident at all; this is about as close to a random guess you could get

b. I can be a little confident; it might be close, or it might by way off

c. I can be very confident; it will be close, but it probably won't be exact

d. I can be certain that my predicted value will match the actual value exactly

I think it's c, but I'm not so sure. Please help :)