An article is sold at a certain price. If it is sold at 70% of this price, then there is a loss of 10%. What is the percentage profit, when it is sold at the original selling price?

A

$$\frac{100}{7}\%$$

B

$$\frac{50}{7}\%$$

C

$$\frac{300}{7}\%$$

D

$$\frac{200}{7}\%$$