Some Courts Require Additional Information to Establish the Veracity/truthfulness of an Ordinary

Some courts require additional information to establish the veracity/truthfulness of an ordinary citizen informant if the citizen merely provides an anonymous tip. Which issue is a primary factor, mentioned in the text (State v. White, Ga. App. 1990) , used by Georgia courts to assess the veracity/truthfulness of an anonymous tip?

A) the testimony of the officer receiving the tip as to its credibility
B) whether the information is from a "concerned citizen"
C) whether the citizen had provided valid tips in the past
D) whether the tipster had firsthand or secondhand knowledge