Louis chooses a whole number from $$1$$ to $$30$$ at random. What is the probability that the number he chooses is a prime number? 
选项为:A:$$\frac{3}{10}$$.  B:$$\frac{2}{5}$$.  C:$$\frac{1}{6}$$.  D:$$\frac{13}{30}$$.  E:$$\frac{1}{3}$$  请回答其中一个选项.