Meaning: Harmful means causing or capable of causing damage or injury.

Wrong options:

• accomplished: 'Accomplished' is an adjective that refers to someone who is highly skilled, which does not fit the context of describing rays.
• contacted: 'Contacted' is a verb that implies reaching out to someone, which does not relate to the nature of ultraviolet rays.
• deposed: 'Deposed' is a verb that means to remove from office or power, which is irrelevant in this context.
• developed: 'Developed' is a verb that indicates growth or advancement, which does not describe the rays themselves.
• exposed: 'Exposed' is a verb that means to make something visible or reveal it, which does not fit as a description of rays.

Correct answer: exposed

Explanation: The term 'exposed' is a past participle used here to indicate that people are subjected to sunlight. It fits grammatically as it describes the action of being in sunlight and aligns with the context of vitamin D production.

Meaning: Exposed means to be made visible or subjected to something, in this case, sunlight.

Wrong options:

• accomplished: 'Accomplished' does not fit as it refers to achieving something, which is not relevant to the action of being in sunlight.
• contacted: 'Contacted' implies reaching out to someone, which does not relate to the context of sunlight exposure.
• deposed: 'Deposed' refers to being removed from power, which is unrelated to the context of sunlight.
• developed: 'Developed' is a verb that indicates growth or advancement, which does not describe the action of being in sunlight.

Correct answer: developed

Explanation: The word 'developed' is a verb that indicates a gradual change or evolution over time. It fits grammatically as it describes the action of people acquiring light-colored skin and aligns with the context of adaptation to sunlight conditions.

Meaning: Developed means to grow or cause to grow and become more mature or advanced.

Wrong options:

• accomplished: 'Accomplished' refers to achieving a goal, which does not fit the context of skin color change.
• contacted: 'Contacted' implies reaching out to someone, which is irrelevant in this context.
• deposed: 'Deposed' means to remove from office or power, which does not relate to skin color development.
• exposed: 'Exposed' is a verb that means to reveal or make visible, which does not fit the context of skin adaptation.