Humint or Human Intelligence.

Ground Truthing is used to verify Remote sensing and is also known as HUMINT, or human intelligence.

Human intelligence (HUMINT) targeting methods include recruitment of sources, conducting surveillance, eliciting information through conversations or interviews, and using covert means to gather intelligence. These methods involve understanding the target's vulnerabilities, motivations, and potential for cooperation to collect relevant information. Targeting may involve both overt and covert activities to maximize intelligence collection.

Humint

humint is not correct

OSINT is the correct answer