Critical Reasoning

In Arumville, among those young children with elevated levels lead in their
blood, few leave in houses containing lead-based paint, but many leave in
areas where vehicular traffic is heavy. These children's elevated blood-lead
levels probably result from lead added to gas, since, although gasoline sold in and around Arumville has been lead-free since 1990, lead from vehicule exhaust
remains in the soil for many years.

Which of the following, if true, most strengthens the argument?

A: Sale of lead-based paint for use in homes was banned in Arumville in 1977

B: Vehicle traffic in most residential areas of Arumville is heavier today than it was twenty years ago

C: Some lead in the soil comes from deteriorating lead-based paint on the exterior of buildings

D: In Arumville, children's blood-lead levels typically rise during the warm summer months when children frequently play outdoors but not in the winter when children spend more time indoors.

E: If improperly carried out, the removal of lead-based paint from older houses can significantly the risk that children living in such houses will ingest lead dust.

Conclusion: Lead remains in the soil leads to elevated lead levels among children(although lead is banned after 1990)

Couple of the assumptions are:
-Currently running vehicles don't release lead into the air.
-These children don't spend lot of their time in places, such as schools, that have lead paint.


Coming to choice B, can this be a good weakener ?
I think it attacks the first assumption I noted.

If not B, what could be a strong weakener ?

gocoder wrote:In Arumville, among those young children with elevated levels lead in their
blood, few leave in houses containing lead-based paint, but many leave in
areas where vehicular traffic is heavy. These children's elevated blood-lead
levels probably result from lead added to gas, since, although gasoline sold in and around Arumville has been lead-free since 1990, lead from vehicle exhaust remains in the soil for many years.

Which of the following, if true, most strengthens the argument?

A: Sale of lead-based paint for use in homes was banned in Arumville in 1977

B: Vehicle traffic in most residential areas of Arumville is heavier today than it was twenty years ago

C: Some lead in the soil comes from deteriorating lead-based paint on the exterior of buildings

D: In Arumville, children's blood-lead levels typically rise during the warm summer months when children frequently play outdoors but not in the winter when children spend more time indoors.

E: If improperly carried out, the removal of lead-based paint from older houses can significantly the risk that children living in such houses will ingest lead dust.

This CR links lead IN SOIL to lead IN CHILDREN.
The correct answer choice must strengthen this link.

D: In Arumville, children's blood-lead levels typically rise during the warm summer months when children frequently play outdoors but not in the winter when children spend more time indoors.
Here, blood-lead levels increase when children play OUTDOORS and are exposed to SOIL, strengthening the link between lead in the soil and increased blood-lead levels in children.

The correct answer is D.

B: Vehicle traffic in most residential areas of Arumville is heavier today.
Since gas has been lead-free since 1990, the amount of traffic today is irrelevant.
The argument believes that lead in soil emanated not from CURRENT traffic but from vehicles driven BEFORE 1990.
Eliminate B.