Yep, I agree with Bengolds..;and not to mention..but a few other infos are missing..anyway the reading must be higher than the one published..and so for..the only one acceptable is the "A"..
As mentioned, they only want a check your understanding about the influence of the actual T°...
You're quite lucky..It coulld have been:
a: 1765
b: 1780
c: 1835
rgds