Meaning: 'Hijack' means to take control of something, often in a forceful or unexpected way, suggesting that smartphones seize our basic human desires.

Wrong options:

• describe: 'Describe' means to explain or detail something, which does not fit the context of taking control of desires.
• sharpen: 'Sharpen' implies making something more acute or intense, which does not align with the idea of controlling desires.
• conserve: 'Conserve' means to protect or preserve something, which contradicts the notion of taking control of our desires.

Correct answer: of

Explanation: The preposition 'of' correctly indicates the relationship between smartphones and the category of bestselling devices, fitting grammatically and contextually within the sentence structure.

Meaning: 'Of' is used to show belonging or association, indicating that smartphones are part of the bestselling devices category.

Wrong options:

• an: 'An' is an article that cannot function as a preposition in this context, making it grammatically incorrect.
• in: 'In' suggests inclusion within a space or category, which does not accurately convey the relationship here.
• on: 'On' typically indicates a surface or a topic, which does not fit the intended meaning of belonging to a category.

Correct answer: staring

Explanation: The gerund 'staring' fits grammatically as it describes the action we are doing with our screens. It aligns contextually with the idea of spending time focused on something, which is appropriate in this context.

Meaning: 'Staring' means looking fixedly or vacantly at something, indicating prolonged attention to the screens.

Wrong options:

• watching: 'Watching' implies active engagement with content, which is not as fitting as 'staring' in the context of passive screen time.
• waggling: 'Waggling' means to move something rapidly back and forth, which does not relate to the action of looking at screens.
• snoring: 'Snoring' refers to a sound made during sleep, which is irrelevant to the context of screen usage.

Correct answer: evaporating

Explanation: The present participle 'evaporating' fits grammatically as it describes an ongoing action, aligning with the context of time disappearing. It suggests that time is continuously slipping away, which is relevant to the discussion of underestimating phone usage.

Meaning: 'Evaporating' means disappearing gradually, which metaphorically describes how time spent on phones is often underestimated.

Wrong options:

• has evaporated: 'Has evaporated' is in the present perfect tense, which does not match the ongoing nature of the action described in the sentence.
• evaporates: 'Evaporates' is in the simple present tense, which does not convey the continuous aspect needed here.
• evaporating: This option is actually the correct answer, so it cannot be considered a wrong option.