Meaning: 'Unscathed' means not harmed or damaged, suggesting that the motorcyclist has come through the accident without injury.

Wrong options:

• narrowly: 'Narrowly' implies a close call or near miss, which does not fit the context of escaping injury as it suggests a level of risk rather than safety.
• incompletely: 'Incompletely' refers to something not being finished or done fully, which does not relate to the idea of avoiding injury in an accident.
• fined: 'Fined' means to be penalized financially, which is unrelated to the physical state of the motorcyclist after an accident.

Correct answer: sustain

Explanation: The verb 'sustain' is appropriate here as it means to suffer or experience something, particularly injuries. It fits grammatically in the context of the sentence, which discusses the unfortunate outcomes of accidents.

Meaning: 'Sustain' means to endure or experience something negative, such as injuries in this case.

Wrong options:

• spend: 'Spend' refers to using time or money, which does not relate to experiencing injuries and is grammatically incorrect in this context.
• forbid: 'Forbid' means to prohibit or prevent, which does not fit the context of experiencing injuries.
• expect: 'Expect' means to anticipate something, which does not align with the context of suffering injuries.

Correct answer: operational

Explanation: The word 'operational' indicates that the motorcycle is functioning and ready for use, which is contextually relevant as it describes the prototype's status. It fits grammatically as it describes the state of the motorcycle.

Meaning: 'Operational' means that something is in working order and can be used as intended.

Wrong options:

• invented: 'Invented' refers to the creation of something new, which does not describe the current state of the motorcycle as it is already a prototype.
• expensive: 'Expensive' describes the cost of something, which is not relevant to the functionality of the motorcycle.
• exempted: 'Exempted' means to be freed from an obligation or rule, which does not apply to the context of the motorcycle's operational status.

Correct answer: suit

Explanation: The verb 'suit' is appropriate as it means to be appropriate or fitting for someone, which aligns with the context of modifying the motorcycle for riders with specific needs. It fits grammatically as it describes the purpose of the modifications.

Meaning: 'Suit' means to be right or appropriate for a particular person or purpose.

Wrong options:

• shape: 'Shape' refers to forming or molding something, which does not convey the idea of appropriateness for the riders.
• reform: 'Reform' means to change something for the better, which does not fit the context of making the motorcycle appropriate for riders.
• avoid: 'Avoid' means to keep away from something, which does not relate to the idea of making the motorcycle suitable for riders.