Which option represents a common choice among students based on the text's implication?

The choice of walking to school is representative of a common choice among students, as suggested by the text's implication. Walking is often viewed as a practical and accessible option for many students who live within a reasonable distance from their school. It allows for additional physical activity, can be a cost-effective alternative to using transport, and also offers the opportunity for social interaction with peers who might choose to walk as well.

The other options, while they may also be common activities, do not capture the same level of personal choice or routine behavior as walking. Using public transport may not apply to everyone, as it depends on several factors including location and availability. Carrying books is a necessity rather than a choice and does not reflect the same active decision-making process. Reading on the bus represents a specific behavior rather than a broader choice, as it depends on the availability of public transport and the individual preference to read during transit. Thus, walking to school stands out as a more universal and relatable option among students.