Meaning: 'Based' means to have a foundation or starting point in something, in this case, the vaccines are founded on mRNA technology.

Wrong options:

• awarded: 'Awarded' is the past tense of 'award,' which does not fit here as it does not describe the vaccines' development.
• groundwork: 'Groundwork' is a noun referring to the foundation or basis for something, which does not fit grammatically in this verb context.
• equipment: 'Equipment' is a noun that refers to tools or machinery, which is unrelated to the context of vaccine development.
• measure: 'Measure' is a noun or verb that refers to the act of determining size or quantity, which does not apply to the context of vaccines.
• risen: 'Risen' is the past participle of 'rise,' which does not relate to the development of vaccines and is grammatically incorrect here.
• notice: 'Notice' is a noun that refers to awareness or attention, which does not fit the grammatical structure of the sentence.

Correct answer: notice

Explanation: The word 'notice' serves as a noun that indicates the awareness or attention given to the emergence of COVID-19. It fits contextually as it describes when the disease first became known to the world.

Meaning: 'Notice' refers to the act of becoming aware of something, in this case, the world becoming aware of COVID-19.

Wrong options:

• awarded: 'Awarded' is a verb that does not fit in this context as it does not relate to the awareness of the disease.
• groundwork: 'Groundwork' is a noun that refers to foundational work, which does not apply to the context of awareness.
• equipment: 'Equipment' is a noun that refers to tools or machinery, which is unrelated to the concept of awareness.
• measure: 'Measure' is a noun or verb that refers to the act of determining size or quantity, which does not apply to the context of awareness.
• risen: 'Risen' is the past participle of 'rise,' which does not relate to the context of awareness and is grammatically incorrect here.
• based: 'Based' is a past participle that describes the foundation of something, which does not fit the context of awareness.

Correct answer: groundwork

Explanation: The term 'groundwork' is a noun that refers to the foundational work necessary for the development of mRNA vaccines. It fits contextually as it describes the essential contributions made by the biochemists.

Meaning: 'Groundwork' refers to the basic work or preparation needed for something to be built or developed, in this case, mRNA vaccines.

Wrong options:

• awarded: 'Awarded' is a verb that does not fit in this context as it does not relate to foundational work.
• equipment: 'Equipment' is a noun that refers to tools or machinery, which is unrelated to the concept of foundational work.
• measure: 'Measure' is a noun or verb that refers to the act of determining size or quantity, which does not apply to the context of foundational work.
• notice: 'Notice' is a noun that refers to awareness or attention, which does not fit the context of foundational work.
• risen: 'Risen' is the past participle of 'rise,' which does not relate to the context of foundational work and is grammatically incorrect here.
• based: 'Based' is a past participle that describes the foundation of something, which does not fit the context of foundational work.

Correct answer: awarded

Explanation: The word 'awarded' is the past participle of the verb 'award,' indicating that the biochemists received recognition for their contributions. This fits grammatically as it describes the action taken regarding the Nobel Prize.

Meaning: 'Awarded' means to have been given something, in this case, the Nobel Prize.

Wrong options:

• groundwork: 'Groundwork' is a noun that refers to foundational work, which does not fit in this verb context.
• equipment: 'Equipment' is a noun that refers to tools or machinery, which is unrelated to the context of receiving an award.
• measure: 'Measure' is a noun or verb that refers to the act of determining size or quantity, which does not apply to the context of receiving an award.
• notice: 'Notice' is a noun that refers to awareness or attention, which does not fit the context of receiving an award.
• risen: 'Risen' is the past participle of 'rise,' which does not relate to the context of receiving an award and is grammatically incorrect here.
• based: 'Based' is a past participle that describes the foundation of something, which does not fit the context of receiving an award.