Which of the following is NOT an example of internal expansion?

A) Shocking Stockings is an Internet-only seller of pantyhose with funky handpainted designs on them. The company found out from a survey it conducted that its customers have a need for practical socks as much as for pantyhose, so it began selling handpainted hiking socks as well. The company also decided to open several retail stores in the northeast.
B) Tom's Turkey Farm was full of turkeys and Tom's took enough orders to completely sell out its stock every Thanksgiving. So Tom's bought 50 more acres of land a few towns away from its original farm, built barns, and began raising twice as many turkeys as it had raised before.
C) Clara sold handmade greeting cards out of her house. Carl's Custom Cards liked Clara's work so much it purchased her company and gave Clara a job so she could continue to create her beautiful cards.
D) Millie makes mittens to sell to local schools, which give the mittens to children who don't have any. Last year one of the schools asked Millie if she would also make hats, as several children were coming to school with very red, cold ears. So now Millie makes both hats and mittens for the schoolchildren.
E) Lefty Louisa's sells products made for left-handed people. Originally Louisa had only one storefront. The business grew to seven stores, and over the years more and more people began calling and asking for products to be shipped to them. So Louisa now has a Web site through which she sells her left-handed products.

Answer: C
Explanation: C) The purchase of Clara's card business by Carl's Custom Cards is an example of an acquisition, which is a type of external expansion.