Which of the following is a method used by scientists to gather evidence during an infectious disease outbreak?

Bioinformatics is a key method used by scientists to gather evidence during an infectious disease outbreak because it involves the use of computational tools and methods to analyze biological data, particularly genetic material from pathogens. By applying bioinformatics, researchers can examine the genetic sequences of viruses or bacteria, track mutations, and identify how the pathogen is related to others, which is crucial in understanding transmission patterns, virulence, and potential resistance to treatments.

This approach allows for the rapid processing of large amounts of genomic data, making it easier to trace outbreaks and inform public health responses. Bioinformatics can also play a role in vaccine development and therapeutic approaches by identifying targets for intervention based on the pathogen's genetic makeup.

In contrast, the other options—biometrics (focused on measurement of biological traits for security purposes), biochemistry (studying chemical processes in living organisms), and biosynthesis (the production of complex molecules from simpler ones in biological systems)—although relevant in their own contexts, do not focus directly on the data analysis and evolutionary tracking needed during an outbreak response. Thus, bioinformatics stands out as the most relevant and effective tool for gathering critical evidence during infectious disease outbreaks.