How did ddt nearly drive the peregrine falcon to extinction in the 1950s and 60s?
a. reproductive disruption
b. blindness
c. cancer
d. feather loss

DDT nearly drove the Peregrine Falcon to extinction in the 1950s and 60s by disrupting their reproductive cycle. The falcon's prey would eat the insects sprayed with DDT and then the falcon would eat infected the prey. The falcon then laid eggs with very thin shells which were crushed when the female bird sat on them. 
DDT is an insecticide and pesticide that does not break down in the environment. It stays active throughout many cycles of life. This can be seen in the above example.