When considering external storage devices that John may want to secure as evidence while writing a search warrant, the BEST example would be a hard drive in a computer. This is because a hard drive in a computer is a physical device that stores data locally on the computer itself. By securing the hard drive, John can preserve important evidence that might be crucial to his investigation.
Other examples of external storage devices that John may find onsite include a thumb drive. A thumb drive is a portable storage device that can be easily connected to a computer to transfer or store data. If John comes across a thumb drive during his search, it could contain valuable evidence that needs to be secured for further analysis.
In contrast, cloud storage is not a physical external storage device that John would find onsite. Cloud storage refers to online storage services where data is stored remotely on servers accessed through the internet. While cloud storage can be important for digital evidence, it is not a physical device that John would physically secure onsite.
Lastly, a headset is not an external storage device but rather a peripheral used for audio input and output. John would not need to secure a headset as evidence for his search warrant related to storage devices.