Meaning: 'Challenges' means to question or dispute something, in this case, the existing understanding of attention and sensory information prioritization.

Wrong options:

• annoys: 'Annoys' implies causing irritation, which does not fit the context of scientific inquiry and understanding.
• tests: 'Tests' suggests an experimental approach but lacks the nuance of questioning existing knowledge, making it less suitable here.
• adds: 'Adds' implies simply contributing information, which does not convey the critical aspect of questioning or contesting existing views.

Correct answer: Previous

Explanation: The word 'Previous' is an adjective that correctly modifies 'studies,' indicating that the studies being referred to occurred before the current research, fitting grammatically and contextually in the sentence.

Meaning: 'Previous' means something that occurred before the present time, indicating that earlier studies did not consider individual factors.

Wrong options:

• First: 'First' implies the initial occurrence, which does not accurately describe studies that have already been conducted prior to the current one.
• Before: 'Before' is a preposition that does not grammatically fit as a modifier for 'studies' in this context.
• One-time: 'One-time' suggests a singular occurrence, which does not apply to the multiple studies being referenced.

Correct answer: participants

Explanation: The word 'participants' is a noun that fits grammatically as it refers to individuals involved in the study, aligning well with the context of research subjects watching videos.

Meaning: 'Participants' refers to individuals who take part in a study or experiment, in this case, those watching the videos.

Wrong options:

• beings: 'Beings' is a broad term that refers to living entities and does not specifically denote individuals involved in a study, making it too vague.
• players: 'Players' typically refers to individuals in a game or sport, which does not fit the context of a research study.
• characters: 'Characters' implies fictional or dramatic figures, which is not appropriate in the context of real individuals participating in research.

Correct answer: drawing

Explanation: The word 'drawing' is a present participle that fits grammatically and contextually, indicating that the pedestrians and cars are actively attracting attention away from the conversation.

Meaning: 'Drawing' means to attract or pull attention towards something, in this case, away from the filmed conversation.

Wrong options:

• interesting: 'Interesting' is an adjective that does not fit grammatically as it cannot function as a verb in this context.
• bringing: 'Bringing' suggests a transfer of attention but does not convey the active nature of attracting attention as effectively as 'drawing.'
• paying: 'Paying' is a gerund that typically requires a different construction and does not fit well in this context.

Correct answer: tended

Explanation: The word 'tended' is the past tense of the verb 'tend,' which fits grammatically and contextually, indicating a habitual action of women being more distracted by others entering the frame.

Meaning: 'Tended' means to have a tendency or inclination towards something, in this case, being distracted by other people.

Wrong options:

• accept: 'Accept' implies agreement or approval, which does not fit the context of distraction.
• preferred: 'Preferred' suggests a choice or liking, which does not accurately describe the action of being distracted.
• elect: 'Elect' means to choose or decide, which does not apply to the context of distraction in this sentence.