Which of the following best describes black tar heroin?

Black tar heroin is primarily characterized by its unique physical appearance, which is sticky and resembles tar, consistent with its name. This form of heroin is typically produced from the crude processing of opium and can vary in consistency, often appearing as a black or dark brown substance. The sticky texture and tar-like appearance are distinguishing features that set it apart from other forms of heroin, such as white powder heroin, which is usually more easily dissolvable and does not have the same sticky characteristics.

The other options do not accurately describe black tar heroin. While it can have a range of colors, it is not always brown. Additionally, describing it as a liquid form would be misleading, as it is solid but can have a gooey consistency. The notion that black tar heroin is the same as white powder heroin is also incorrect, as they differ significantly in their composition, production methods, and overall effects. Therefore, the assertion that it is sticky and resembles tar best captures the essence of what black tar heroin is.