Using microorganisms to break down synthetic pollutants such as polychlorinated biphenyls (PCBs) is specifically termed: (Choose the most accurate environmental engineering term.)

Introduction:
PCBs are persistent organic pollutants. Certain microbial processes can transform or mineralize them under controlled conditions. This question asks for the correct term describing such applied microbial cleanup.

Given Data / Assumptions:

• Biotransformation may be aerobic (cometabolism) or anaerobic (reductive dechlorination).
• Field implementation requires attention to electron donors/acceptors, nutrients, and bioavailability.
• Goal: reduce mass, toxicity, mobility, or exposure risk.

Concept / Approach:
“Bioremediation” encompasses natural attenuation, biostimulation, and bioaugmentation strategies aimed at contaminant cleanup. While “biotechnology” is broader, and “bioinformatics” involves data analysis, bioremediation precisely denotes using microbes to remediate pollutants like PCBs.

Step-by-Step Solution:
Identify the task: microbial degradation/transformation of pollutants. Map to terminology: the environmental cleanup term is bioremediation. Eliminate unrelated fields (informatics, gene delivery). Select the term that directly indicates cleanup of contaminants.

Verification / Alternative check:
Remedial action plans cite anaerobic PCB dechlorination and aerobic polishing as bioremediation approaches.

Why Other Options Are Wrong:

• Bioinformatics: Computational biology; not cleanup.
• Biolistics: Particle bombardment for gene transfer.
• Biotechnology: Overly broad; not specific to cleanup.

Common Pitfalls:
Using “biotechnology” when a precise term is required for environmental applications.

Final Answer:
bioremediation is the correct term.