There is a box containing~$7$ chips numbered $1$, $2$, $3$, $4$, $5$, $6$, and $7$. A chip is drawn randomly from the box. What is the probability that the number on the chip is an even number? (adapted from 2015 AMC 8 Problem, Question \#7) 
选项为:A:$\frac17$  B:$\frac37$  C:$\frac57$  D:$\frac47$  E:$\frac67$  请回答其中一个选项.