Which of the following can be considered physical evidence?

Physical evidence is defined as any material object that can be physically examined and can contribute to establishing facts in a criminal investigation. This type of evidence can be anything tangible that can be linked to the crime or the suspect, providing valuable information for analysis.

In this context, weapons are a clear example of physical evidence. They can be collected from the crime scene, analyzed for fingerprints, DNA, or other trace evidence, and used to connect a suspect to a crime. The presence of a weapon can often play a critical role in establishing the circumstances surrounding a criminal event, including the intent and potential implications of the crime committed.

On the other hand, while witness testimonies, surveillance footage, and alibis are indeed significant in investigations, they are not classified as physical evidence. Witness testimonies rely on individuals recounting their experiences and perceptions, which can be subjective. Surveillance footage, while often video evidence, is typically classified as documentary evidence rather than physical evidence. Alibis involve claims about a suspect's whereabouts and do not consist of tangible items that can be physically analyzed. Thus, weapons stand out as the correct choice, exemplifying the concept of physical evidence in a criminal investigation.