Answer:
2. the trachea widens and lengthens.
Explanation:
Moist, smooth tissue called mucosa lines the inside of the trachea. The trachea widens and lengthens slightly with each breath in, returning to its resting size with each breath out.
The correct answer is D.
An increase in Lyme disease does not cause an increase in drowning. There may be a correlation between the two but there is no causation. The likely lurking variable that would cause an increase in Lyme disease would be temperature as people are more likely to venture out into the woods and for walks in long grass with their pets when the weather is nice and could contract the disease from the ticks in the woods and grasslands. The lurking variable that would cause an increase in drowning would be time of the year as once again when the weather is nice people go swimming which can lead to drowning if not careful.
