With the decision made, Rankin, a 5-foot-11, 179-pound athlete from Salisbury (N.C.), called Everett Withers, UNC's defensive coordinator, shortly before noon on Wednesday.
"He was very excited," Rankin said. "He has me and another freshman, [Brandon Ellerbe], coming in at safety. He seemed very excited about my commitment."
Rankin earned a UNC scholarship offer with his performance at the Tar Heels' camp last month.
Besides UNC, Rankin also received scholarship offers from Kent State and Utah, and significant interest from NC State, South Carolina, and Wake Forest.
"[New offers] won't change my commitment," Rankin said. "I'm committed; I'm going to stay committed to North Carolina."
The only school Rankin plans to visit is UNC.
"They told me to come up [when I can] to meet more of the players and talk to Butch Davis," Rankin said.
Besides earning a scholarship offer, the Tar Heels' camp provided Rankin an opportunity to see UNC's family atmosphere.
"[I liked] the way when I went in there for camp they just treated me as their family – like I was already playing for them," Rankin said. "I just liked how they treated me. They showed me much respect."
Rankin's teammate, Romar Morris, also has a UNC scholarship offer and lists the Tar Heels among his five favorite schools.
"I'm talking to him about it, but I don't know where his head is going to be," Rankin said. "His head is still in the middle."
Rankin plans to recruit Morris to UNC.
"I don't want to pressure him to go anywhere he doesn't want to go," Rankin said. "But I would love to have him as my teammate, again."