The Recent Increase in the Rate of Diagnosis of Autism

The recent increase in the rate of diagnosis of autism coincides with:

A) A deterioration in the quality of diagnostic training that clinicians receive
B) An increase in the uptake of the MMR vaccine
C) An increase in the prevalence of children's illnesses associated with the digestive system
D) The use of a radically new system of diagnosis that is vulnerable to false positives
E) A decrease in diagnosing general learning disabilities