Meaning: Evolved means to develop gradually, especially from a simple to a more complex form.

Wrong options:

• adapted: 'Adapted' is also a past participle but implies a change in response to specific conditions rather than a gradual development over time, making it less suitable here.
• despite: 'Despite' is a preposition used to indicate contrast, which does not fit grammatically or contextually in this sentence.
• postponed: 'Postponed' is the past participle of 'postpone,' meaning to delay, which does not relate to the context of evolution or development.
• thanks: 'Thanks' is a noun or interjection expressing gratitude, which does not fit as a verb in this context.
• sustained: 'Sustained' is a past participle meaning maintained over time, but it does not convey the idea of gradual development like 'evolved' does.

Correct answer: thanks

Explanation: The word 'thanks' serves as a preposition in this context, indicating the reason for the changes in our nights. It fits grammatically and contextually as it introduces the cause of the transformation due to electric light.

Meaning: Thanks means as a result of or due to something.

Wrong options:

• evolved: 'Evolved' is a verb that does not fit grammatically in this context, as it does not serve to indicate a reason or cause.
• despite: 'Despite' is a preposition indicating contrast, which does not fit the context of explaining a cause for the changes in night.
• postponed: 'Postponed' is a verb that does not relate to the context of causation and does not fit grammatically.
• sustained: 'Sustained' is a past participle that does not convey the idea of causation and does not fit in this context.
• allowed: 'Allowed' is a verb that does not serve to indicate a reason and does not fit grammatically.

Correct answer: allowed

Explanation: The word 'allowed' is the past participle of 'allow,' which fits grammatically as it indicates that light has enabled humans to do something. It aligns with the context of discussing the impact of light on human activities during the night.

Meaning: Allowed means to permit or enable something to happen.

Wrong options:

• adapted: 'Adapted' is a past participle that implies a change in response to conditions, which does not fit the context of enabling actions.
• evolved: 'Evolved' suggests a gradual development rather than the enabling action that 'allowed' conveys, making it less suitable here.
• despite: 'Despite' is a preposition indicating contrast, which does not fit grammatically or contextually in this sentence.
• thanks: 'Thanks' is a noun or interjection expressing gratitude, which does not fit as a verb in this context.
• sustained: 'Sustained' means maintained over time, which does not convey the enabling action that 'allowed' does.

Correct answer: adapted

Explanation: The word 'adapted' is the past participle of 'adapt,' which fits grammatically as it describes how humans' eyes have changed to suit daylight conditions. It aligns with the context of discussing the suitability of human vision for nighttime activities.

Meaning: Adapted means adjusted or modified to fit new conditions or environments.

Wrong options:

• evolved: 'Evolved' implies a broader development over time rather than the specific adjustment of eyes to daylight, making it less suitable here.
• allowed: 'Allowed' is a past participle that does not describe a change in the eyes but rather an enabling action, which does not fit the context.
• despite: 'Despite' is a preposition indicating contrast, which does not fit grammatically or contextually in this sentence.
• thanks: 'Thanks' is a noun or interjection expressing gratitude, which does not fit as a verb in this context.
• sustained: 'Sustained' means maintained over time, which does not convey the idea of adjustment that 'adapted' does.