Final answer:
Field trials are the studies conducted in the target species to test a drug's safety and efficacy in real-life conditions. They follow pre-clinical studies and clinical trials and are a critical part of the drug development process that helps ensure a drug will perform safely and effectively in the species it is intended for.
Step-by-step explanation:
The term used for studies conducted in the target species to prove that the drug is safe and effective for that species is D) Field trials. Field trials are in vivo studies that take place after the initial pre-clinical studies in animals and the clinical trials in humans are complete. These trials are critical for evaluating the drug's safety and efficacy under conditions that closely resemble real-life usage in the target population. The progression of a drug through its development includes several phases, starting with in vitro experiments, followed by preclinical tests in animals, and then advancing to clinical trials. Field trials come into play after there is sufficient evidence from these initial stages to suggest that the drug could be beneficial in the target species.
While other studies like in vitro and preclinical studies inform pharmacokinetic properties and potential safety concerns, it is the field trials that provide comprehensive data in the context the drug will actually be used. These studies often involve a larger number of subjects and are more reflective of the diverse conditions the drug will encounter once it is approved for general use by regulatory authorities such as the FDA. This information is crucial to gaining a full understanding of the drug's performance and eventual approval for use in the target species.