The pesticide Azocide, introduced to central valley farms three summers ago, has proven ineffective because other pesticides' chemical compositions already in wide use neutralizing its desired effect.
A.because other pesticides chemical compositions already in wide use
B.because of the chemical compositions of the pesticides already in wide use
C.due to other pesticides already in wide use, whose chemical compositions have been
D.since, due to the chemical compositions of the other pesticides already in use, those pesticides have been
E. because of other pesticides and their chemical compositions already in use, which have been
In D use of 'due to' is wrong.
In E the meaning is changed. Pesticides are in use & not their chemical compositions.
A & B are not doing well with 'neutralizing'.
C goes perfect with 'neutralizing' & the second concern, 'due to', is correctly used.