A series of phases used to determine if a new drug is effective and safe for the public is known as what?

The correct answer, clinical trial, refers to a systematic process that involves multiple phases of research designed to evaluate a new drug's efficacy and safety before it can be made available to the public. Clinical trials are critical because they provide evidence-based validation that a drug works as intended and is safe for human use.

These trials start with early-phase studies (Phase I), where the drug is tested on a small group of healthy volunteers to assess safety, followed by Phase II, where the drug's effectiveness is evaluated in a larger group of patients who have the condition the drug aims to treat. Phase III involves even larger populations and further assesses the drug's effectiveness, risks, and benefits in a more diverse group of patients. By the time a drug completes these phases, a substantial amount of data is collected that informs regulatory bodies about the drug's safety profile and therapeutic effectiveness.

The other options do not adequately encompass the structured and regulatory-compliant process involved in bringing a new drug to market. An approval test is not a formally recognized stage in drug development, a laboratory experiment refers more broadly to controlled studies not necessarily involving human subjects, and a phase study is not a specific or standard term used in the context of drug trials.