Meaning: 'Vital' means extremely important or necessary, highlighting the crucial function of green spaces in urban environments.

Wrong options:

• peripheral: 'Peripheral' means relating to or situated on the edge of something, which does not convey the essential nature of the function described.
• negligible: 'Negligible' means so small or unimportant that it can be disregarded, which contradicts the intended meaning of importance in this context.
• secondary: 'Secondary' implies something of lesser importance, which does not align with the significant role urban green spaces play.

Correct answer: meticulously

Explanation: The adverb 'meticulously' describes the careful and precise maintenance of green spaces, fitting well in the context of how these areas should be cared for to achieve their potential benefits.

Meaning: 'Meticulously' means in a way that shows great attention to detail; very thoroughly, emphasizing the importance of careful maintenance.

Wrong options:

• efficiently: 'Efficiently' suggests doing something in a way that maximizes productivity, but does not convey the careful attention implied in the context.
• scarcely: 'Scarcely' means hardly or barely, which contradicts the idea of proper maintenance and does not fit the positive context of the sentence.
• broadly: 'Broadly' means in general terms or widely, which does not accurately describe the specific and careful nature of maintenance required.

Correct answer: ameliorate

Explanation: The verb 'ameliorate' means to make something better or improve, which fits contextually as it describes the positive impact of greenery on mental health.

Meaning: 'Ameliorate' means to improve or make better, particularly in the context of mental health benefits from exposure to green spaces.

Wrong options:

• detract from: 'Detract from' means to take away from or reduce the value of something, which is the opposite of the intended meaning of improvement.
• exacerbate: 'Exacerbate' means to make a problem worse, which contradicts the positive context of enhancing mental health.
• overlook: 'Overlook' means to fail to notice or consider, which does not fit the context of improving mental health.

Correct answer: might

Explanation: The modal verb 'might' indicates a possibility, which is appropriate in the context of suggesting potential improvements in public health from prioritizing green spaces.

Meaning: 'Might' expresses a possibility or potential, indicating that improvements in public health are not guaranteed but possible.

Wrong options:

• could: 'Could' also indicates possibility but lacks the nuance of uncertainty that 'might' conveys in this context.
• should: 'Should' implies a recommendation or obligation, which does not fit the speculative nature of the statement about potential improvements.
• will: 'Will' indicates certainty, which is too strong for the context that discusses potential outcomes.

Correct answer: accessible

Explanation: The adjective 'accessible' describes something that is easy to approach or reach, which is essential in the context of ensuring that all residents can benefit from urban green spaces.

Meaning: 'Accessible' means easy to reach or use, emphasizing the importance of making green spaces available to everyone in the community.

Wrong options:

• beneficial: 'Beneficial' means producing good results or helpful effects, which does not fit grammatically as it does not describe the physical accessibility of the spaces.
• detrimental: 'Detrimental' means causing harm or damage, which is the opposite of what is intended in the context of urban planning.
• indifferent: 'Indifferent' means having no particular interest or concern, which contradicts the need for urban spaces to be welcoming and usable by all residents.