Which of the following models uses a directed graph to specify the rights that a subject can transfer to an object or that a subject can take from another subject? 

Answer options:

A. Take-Grant Protection Model
B. Biba Integrity Model
C. Bell-LaPadula Model
D. Access Matrix

rules describing admissible changes of the graph. Answer: D is incorrect. The access matrix is a straightforward approach that provides access rights to subjects

The take-grant protection model is a formal model used in the field of computer security to establish or disprove the safety of a given computer system that follows specific rules. It shows that for specific systems the question of safety is decidable in linear time, which is in general undecidable. The model represents a system as directed graph, where vertices are either subjects or objects. The edges between them are labeled and the label indicates the rights that the source of the edge has over the destination. Two rights occur in every instance of the model: take and grant. They play a special role in the graph rewriting address additional integrity requirements.