A.I. Explanation:

Correct answer: blend

Explanation: The word 'blend' fits grammatically as it is a verb that describes the action of mixing in with the surroundings, which aligns with the context of the nightjar's plumage helping it to camouflage. The sentence structure requires a verb that indicates how the nightjar integrates with its environment, making 'blend' the most suitable choice.

Meaning: 'Blend' means to mix or combine smoothly with something else, in this case, the nightjar's plumage with its surroundings.

Wrong options:

• sneak: The word 'sneak' implies stealthy movement rather than the action of camouflaging, making it contextually inappropriate here.
• pride: 'Pride' is a noun that does not fit grammatically as it does not convey an action related to the nightjar's camouflage.
• scream: 'Scream' is a verb that indicates a loud vocalization, which is irrelevant to the context of blending in with surroundings.

Correct answer: makes

Explanation: The verb 'makes' is appropriate here as it indicates the action of creating or establishing the nightjar's status as a camouflage champion. It fits grammatically and contextually, as the sentence discusses the bird's judgment in choosing backgrounds.

Meaning: 'Makes' means to cause something to happen or to create a particular state, in this case, the bird's ability to camouflage effectively.

Wrong options:

• rates: 'Rates' suggests evaluating or assessing, which does not fit the context of creating a camouflage champion.
• demands: 'Demands' implies a requirement or necessity, which does not align with the context of the bird's choice in backgrounds.
• wants: 'Wants' indicates desire, which is less precise than 'makes' in describing the action of establishing camouflage.

Correct answer: based

Explanation: The word 'based' is correctly used here as it indicates that the bird's nesting choices are determined by its specific patterns and colors. This fits grammatically and contextually, as it describes the foundation of the bird's decision-making process.

Meaning: 'Based' means to use something as a foundation or starting point for a decision or action, in this case, the bird's nesting choices.

Wrong options:

• accordiing: 'Accordiing' is a misspelling of 'according' and does not fit grammatically or contextually in this sentence.
• for: 'For' is a preposition that does not convey the necessary relationship between the bird's choices and its patterns and colors.
• raised: 'Raised' is a past participle that does not fit the context of determining choices based on patterns.

Correct answer: both

Explanation: The word 'both' is suitable here as it indicates that the individual birds enhance their markings in two distinct ways: within a habitat and at a fine scale. This fits grammatically and contextually, as it emphasizes the dual aspects of their camouflage strategy.

Meaning: 'Both' refers to two items or aspects being considered together, in this case, the two ways the birds enhance their camouflage.

Wrong options:

• seldom: 'Seldom' means rarely, which does not fit the context of describing how birds enhance their markings.
• crisis: 'Crisis' refers to a time of intense difficulty or danger, which is irrelevant to the context of camouflage.
• seldomly: 'Seldomly' is an adverb form of 'seldom' and does not fit grammatically or contextually in this sentence.