The difference in temperature between 100°c and 101°c is the difference between 100k and 101k.

The missing word is "equal".

In fact, The relationship between temperature in Celsius and temperature in Kelvin is

So, the absolute value of the two temperatures are different. However, there is a direct proportionality between the temperature in Celsius and the temperature in Kelvin, this means that temperature differences are equal in both units.

Let's see this with an example: let's call and two different temperatures in Celsius, and let's rewrite them in Kelvin using the previous relationship:

as we can see, both the 273.15 cancel out and so the temperature difference in Celsius is equal to the temperature difference in Kelvin.