Scientific techniques used in connection with the detection of crime

Physical Matching

Fingerprint Matching

Hair and fibre analysis

Ballistic Analysis

Blood Spatter Analysis

DNA Analysis

Forensic Pathology

Chemical Analysis

Forensic Anthropology

Forensic Entomology

Forensic Odontology

Forensic Engineering

Criminal Profiling

Geographic Profiling

Forensic Data Analysis

Forensic Document Analysis

Forensic Identification Sections

Crime Detection Laboratories

Explanation:

i think its toxic gasses but i could be wrong

answer; i had to look this up and the only one i found was(last only 15 minutes) plz check first and good luck;