Sugar water theory. 1 gram of sugar added each time, and the sugar water gets sweeter. 
Which is the smallest fraction in $$\frac{2020}{2021}$$, $$\frac{2021}{2022}$$, $$\frac{2022}{2023}$$ and $$\frac{2023}{2024}$$? 

a: $$\frac{2020}{2021}$$ 
b: $$\frac{2021}{2022}$$ 
c: $$\frac{2022}{2023}$$ 
d: $$\frac{2023}{2024}$$ 