Carbon Has a Negative Temperature Coefficient of Resistance of -0 $\degree$

Carbon has a negative temperature coefficient of resistance of -0.5 x 10^-3 ( $\degree$ C) ^-1.What temperature increase would result in a resistance decrease of 1% for a carbon resistor?

A) 2 $\degree$ C
B) 20 $\degree$ C
C) 50 $\degree$ C
D) 100 $\degree$ C