Final answer:
Sentence D should be revised to improve syntax and eliminate passive voice by specifying who should address the issue, making it 'If fishermen and policymakers do not address this issue, they will put other animals at risk.'
Step-by-step explanation:
The sentence from the informational article that should be revised to improve syntax and eliminate passive voice is D) "If this is not addressed, other animals will be at risk." This sentence could be rewritten to specify who or what needs to address the issue, thereby removing the passive voice. An example of an improved sentence might be: "If fishermen and policymakers do not address this issue, they will put other animals at risk." This revision clarifies who is responsible for taking action and directly impacts the welfare of other species in the ecosystem.