$2$ potatoes, $3$ peas and $1$ tomato together weigh $18$ lbs. One pea and one tomato together weigh $8$ lbs. $2$ potatoes and $1$ pea together weigh $2$ lbs more than one pea and one tomato weigh together. Each potato weighs the same and each pea weigh the same. How much does one potato weigh? 
选项为:A:$2$ lbs  B:$3$ lbs  C:$4$ lbs  D:$5$ lbs  E:$6$ lbs  请回答其中一个选项.