A.I. Explanation:

Correct answer: excavated

Explanation: The word 'excavated' is a verb that fits grammatically as it describes the action of digging up or uncovering sites. In this context, it aligns with the subject 'less than one percent' and maintains the overall meaning of the sentence regarding the discovery of ancient sites.

Meaning: 'Excavated' means to dig out and remove earth from a site to uncover artifacts or structures.

Wrong options:

• escalated: The word 'escalated' is a verb that means to increase or intensify, which does not fit the context of uncovering archaeological sites.
• mapped: While 'mapped' is a verb that fits the context of locating sites, it does not relate to the action of uncovering them, making it an incorrect choice for this blank.
• necessarily: The adverb 'necessarily' implies something that must happen, which does not fit the grammatical structure or context of the sentence.
• certified: The verb 'certified' means to officially recognize or confirm, which does not relate to the action of uncovering sites and is therefore incorrect.
• yet: The word 'yet' is an adverb that indicates time but does not fit as a verb in this context.

Correct answer: yet

Explanation: The word 'yet' is an adverb that indicates that something has not happened up to the present time. It fits grammatically and contextually as it emphasizes that the sites have not been unearthed until now.

Meaning: 'Yet' is used to indicate that something has not occurred at this point in time.

Wrong options:

• escalated: The word 'escalated' does not fit as it is a verb meaning to increase, which does not relate to the context of time or uncovering sites.
• excavated: The word 'excavated' is a verb that describes the action of digging, which does not fit as an adverb in this context.
• necessarily: The adverb 'necessarily' implies a requirement, which does not fit the context of indicating time or occurrence.
• certified: The verb 'certified' means to officially recognize, which does not relate to the context of time or the action of uncovering sites.
• mapped: The word 'mapped' is a verb that refers to creating a map, which does not fit the context of indicating something that has not happened.

Correct answer: mapped

Explanation: The word 'mapped' is a verb that fits grammatically as it describes the action of creating a map of the sites. It aligns with the context of locating and organizing information about the Egyptian sites.

Meaning: 'Mapped' means to create a visual representation of an area or to organize information about it.

Wrong options:

• escalated: The word 'escalated' does not fit as it means to increase or intensify, which is unrelated to the action of organizing or locating sites.
• excavated: While 'excavated' is relevant to uncovering sites, it does not fit in this context where the focus is on mapping rather than digging.
• necessarily: The adverb 'necessarily' does not fit as it implies a requirement, which does not relate to the action of mapping sites.
• certified: The verb 'certified' means to officially recognize, which does not relate to the action of mapping or locating sites.
• yet: The word 'yet' is an adverb indicating time and does not fit as a verb in this context.