You only get one birthday present from your parents. Initially, you thought it was twice as likely that your parents would give you a phone for your birthday rather than something else. Then you see the gift-wrapped box, which resembles a cell-phone box in size and shape. The probability of the box looking like this if it were a phone, you decide, is 90%, whereas the probability of it looking this way if it were not a phone is 30%. Updating on this new evidence, what are the odds that you got a phone?

a 6 : 7

b 2 : 1

c 6 : 1

d 5 : 7