A.I. Explanation:

Correct answer: sold

Explanation: The word 'sold' is the past participle of the verb 'sell,' which fits grammatically as it describes the state of smartphones that have been sold in the past. This aligns with the context of discussing the market share of iPhones among smartphones that have already been sold.

Meaning: 'Sold' refers to smartphones that have been purchased by consumers.

Wrong options:

• made: 'Made' is the past participle of 'make,' which does not fit the context as it implies production rather than sales.
• exciting: 'Exciting' is an adjective that describes something that causes excitement, which does not relate to the action of selling.
• fears: 'Fears' is a noun that refers to feelings of anxiety, which does not fit grammatically or contextually in this sentence.
• saturation: 'Saturation' is a noun that refers to a state of being filled to capacity, which does not fit as it does not describe the action of selling smartphones.
• expensive: 'Expensive' is an adjective that describes high cost, which does not relate to the action of selling.

Correct answer: saturation

Explanation: The term 'saturation' refers to the point at which a market is no longer able to absorb more of a product. It fits contextually as it describes the market condition for iPhones among potential customers in developed countries.

Meaning: 'Saturation' indicates a state where demand has been met and no further growth is expected.

Wrong options:

• sold: 'Sold' is a past participle that refers to the action of selling, which does not fit as it does not describe a market condition.
• made: 'Made' is the past participle of 'make,' which does not relate to market saturation.
• continue: 'Continue' is a verb that implies ongoing action, which does not fit the context of describing a market state.
• fears: 'Fears' is a noun that refers to feelings of anxiety, which does not relate to market saturation.
• expensive: 'Expensive' is an adjective that describes high cost, which does not fit as it does not describe a market condition.

Correct answer: continue

Explanation: The word 'continue' is a verb that indicates ongoing action, which fits grammatically and contextually as it describes rival smartphone makers who are persistently challenging Apple.

Meaning: 'Continue' means to persist in an action or process.

Wrong options:

• sold: 'Sold' is a past participle that does not fit as it does not describe an ongoing action.
• made: 'Made' is the past participle of 'make,' which does not convey the idea of ongoing competition.
• fears: 'Fears' is a noun that refers to feelings of anxiety, which does not fit as it does not describe an action.
• saturation: 'Saturation' is a noun that refers to a market condition, which does not fit as it does not describe an action.
• expensive: 'Expensive' is an adjective that describes high cost, which does not relate to the action of challenging.

Correct answer: expensive

Explanation: The word 'expensive' is an adjective that describes the cost of devices. It fits grammatically and contextually as it contrasts with the powerful devices offered by rival smartphone makers.

Meaning: 'Expensive' means having a high price or cost.

Wrong options:

• sold: 'Sold' is a past participle that does not fit as it does not describe the cost of devices.
• made: 'Made' is the past participle of 'make,' which does not relate to the cost of devices.
• continue: 'Continue' is a verb that does not describe the cost of devices and does not fit in this context.
• fears: 'Fears' is a noun that refers to feelings of anxiety, which does not relate to the cost of devices.
• saturation: 'Saturation' is a noun that refers to a market condition, which does not fit as it does not describe cost.