human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "ubuntu one investigation detecting evidences on client machines"):
  Abstract: STorage as a Service (STaaS) cloud services has been adopted by both individuals and businesses as a dominant technology worldwide. Similar to other technologies, this widely accepted service can be misused by criminals. Investigating cloud platforms is becoming a standard component of contemporary digital investigation cases. Hence, digital forensic investigators need to have a working knowledge of the potential evidence that might be stored on cloud services. In this chapter, we conducted a number of experiments to locate data remnants of users' activities when utilizing the Ubuntu One cloud service. We undertook experiments based on common activities performed by users on cloud platforms including downloading, uploading, viewing, and deleting files. We then examined the resulting digital artifacts on a range of client devices, namely, Windows 8.1, Apple Mac OS X, and Apple iOS. Our examination extracted a variety of potentially evidential items ranging from Ubuntu One databases and log files on persistent storage to remnants of user activities in device memory and network traffic.

Includes members:
  Member "digital forensic investigation of cloud storage services":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "greening cloud enabled big data storage forensics syncany as a case study")
  Member "mobile cloud forensics an analysis of seven popular android apps":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "forensics analysis of android mobile voip apps")
  Member "conceptual evidence collection and analysis methodology for android devices":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "forensics analysis of android mobile voip apps")
  Member "calm before the storm the challenges of cloud computing in digital forensics":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "a bleeding digital heart identifying residual data generation from smartphone applications interacting with medical devices")

Question: Please tell me which class the source paper belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.CR(Cryptography and Security)