I have a question!

[cutemina1211]

In the following question,

< > of refuse and garbage at open dumps long remained a major < > of air pollution in many of our cities.

A. Purchasing - result
B. Burning - cause
C. Consideration - concern
D. Collection - benefit
E. Rejection - reason

Please ~. What is an answer?

[Philly]

.
I'd say B (Burning - cause) makes sense.
.

[manikarthik84]

Yes.. Burning - Cause is only fitting

[shemily]

me too think that 'burning' makes sense.