Question

read the passage.
bamboo products such as toothbrushes are often touted as environmentally friendly because they are biodegradable. eco - conscious consumers often choose these alternative products because bamboo toothbrushes decompose in a few months without leaving any harmful waste behind. plastic toothbrushes, on the other hand, can take hundreds of years to break down.
but are bamboo toothbrushes really the most sustainable option? contrary to popular belief, the answer might be no. according to a recent study that analyzed the lifecycle of toothbrushes, plastic manual toothbrushes with replaceable heads beat out bamboo ones. the authors of the study report concerns about how bamboo is cultivated. land used to grow bamboo trees decreases the variety of plants and wildlife that would otherwise thrive in the area. it turns out that there isnt a simple answer to the question of which material makes for a more sustainable toothbrush. bamboo cultivation can be very disruptive to native ecosystems; however, from a climate perspective, bamboo brushes have a lower impact than plastic toothbrushes.
how does the author’s choice to open the second paragraph with a question add to the discussion?

• the question shifts the discussion from one about general consumer choices to one about specific kinds of eco - friendly products.
• the question prompts the reader to consider how sustainability affects product design decisions.
• the question engages the reader by challenging a common assumption about bamboo products.
• the question encourages the reader to think about the environmental costs of using plastic.

Explanation:

1. Analyze the first option: The first paragraph is about bamboo toothbrushes as eco - friendly (consumer choice of eco - friendly products), and the second paragraph's question is about whether bamboo toothbrushes are the most sustainable. The shift is not from general consumer choices to specific eco - friendly products, so this is incorrect.
2. Analyze the second option: The question is about the sustainability of bamboo toothbrushes, not about how sustainability affects product design decisions. So this option is incorrect.
3. Analyze the third option: The first paragraph presents the common belief that bamboo toothbrushes are environmentally friendly. The question “But are bamboo toothbrushes really the most sustainable option?” challenges this common assumption. This engages the reader as it makes them re - evaluate their initial thought about bamboo products.
4. Analyze the fourth option: The question is about bamboo toothbrushes, not about the environmental costs of using plastic. So this option is incorrect.

Answer:

The question engages the reader by challenging a common assumption about bamboo products.