Meaning: 'Theory' refers to a well-substantiated explanation of some aspect of the natural world, based on a body of evidence.

Wrong options:

• originated: 'Originated' is a verb that does not fit as it does not serve as a noun to describe the model.
• relatively: 'Relatively' is an adverb that cannot function as a noun in this context.
• explaining: 'Explaining' is a gerund that does not fit as a noun to describe the model.
• evidence: 'Evidence' is a noun but does not describe the model itself; it refers to the data supporting the theory.
• dating: 'Dating' is a gerund that does not fit as a noun to describe the model.
• analysis: 'Analysis' is a noun but does not accurately describe the model of human population movement.
• perished: 'Perished' is a verb that does not fit grammatically or contextually.

Correct answer: originated

Explanation: The verb 'originated' fits grammatically as it describes the action of modern humans coming into existence in East Africa. It aligns with the context of discussing the beginnings of Homo sapiens.

Meaning: 'Originated' means to have begun or started from a particular place or source.

Wrong options:

• theory: 'Theory' is a noun and does not fit as a verb to describe the action of humans coming into existence.
• relatively: 'Relatively' is an adverb that does not fit as it does not describe an action.
• explaining: 'Explaining' is a gerund that does not fit as it does not convey the action of coming into existence.
• evidence: 'Evidence' is a noun and does not fit as a verb in this context.
• dating: 'Dating' is a gerund that does not relate to the action of originating.
• analysis: 'Analysis' is a noun and does not fit as a verb to describe the action of humans coming into existence.
• perished: 'Perished' is a verb that means to die, which does not fit the context of human origins.

Correct answer: relatively

Explanation: The adverb 'relatively' fits grammatically as it modifies the adjective 'recent,' indicating that the waves of migration are recent in comparison to other time frames. It aligns with the context of discussing the timing of human dispersal.

Meaning: 'Relatively' means in relation or comparison to something else, indicating a degree of recency.

Wrong options:

• theory: 'Theory' is a noun and does not fit as an adverb to modify 'recent.'
• originated: 'Originated' is a verb and does not fit grammatically as it cannot modify 'recent.'
• explaining: 'Explaining' is a gerund and does not fit as it cannot modify 'recent.'
• evidence: 'Evidence' is a noun and does not fit as an adverb to modify 'recent.'
• dating: 'Dating' is a gerund and does not fit as it cannot modify 'recent.'
• analysis: 'Analysis' is a noun and does not fit as an adverb to modify 'recent.'
• perished: 'Perished' is a verb and does not fit as it cannot modify 'recent.'

Correct answer: explaining

Explanation: The gerund 'explaining' fits grammatically as it serves as the action that the proposal is performing, indicating what it does best. It aligns with the context of discussing the proposal's effectiveness in relation to evidence.

Meaning: 'Explaining' refers to the act of making something clear or understandable, particularly in relation to evidence.

Wrong options:

• theory: 'Theory' is a noun and does not fit as a gerund to describe the action of the proposal.
• originated: 'Originated' is a verb that does not fit as it does not convey the action of the proposal.
• relatively: 'Relatively' is an adverb and does not fit as it cannot describe the action of explaining.
• evidence: 'Evidence' is a noun and does not fit as a gerund to describe the action of the proposal.
• dating: 'Dating' is a gerund but does not relate to the action of explaining evidence.
• analysis: 'Analysis' is a noun and does not fit as a gerund to describe the action of the proposal.
• perished: 'Perished' is a verb that does not fit as it does not convey the action of the proposal.

Correct answer: evidence

Explanation: The noun 'evidence' fits grammatically as it serves as the object of the proposal's explanation, referring to the data that supports the theory. It aligns with the context of discussing the basis for the model.

Meaning: 'Evidence' refers to the available body of facts or information indicating whether a belief or proposition is true or valid.

Wrong options:

• theory: 'Theory' is a noun but does not fit as it does not refer to the data supporting the proposal.
• originated: 'Originated' is a verb and does not fit as it cannot serve as a noun in this context.
• relatively: 'Relatively' is an adverb and does not fit as it cannot serve as a noun.
• explaining: 'Explaining' is a gerund and does not fit as it cannot serve as a noun in this context.
• dating: 'Dating' is a gerund and does not fit as it cannot serve as a noun.
• analysis: 'Analysis' is a noun but does not fit as it does not refer to the data supporting the proposal.
• perished: 'Perished' is a verb that does not fit as it does not relate to the concept of evidence.