Prevalence Figures for Behaviour Disorders Indicate All of the Following

Prevalence figures for behaviour disorders indicate all of the following are correct EXCEPT:

A) first- born males are more likely to be classified as behaviourally disordered than are later born males.
B) girls outnumber boys in all categories from mild to severe.
C) diagnosis of ADHD has declined recently resulting in a reduction in numbers.
D) children from working classes are less likely to be regarded as behaviour problems.
E) identification reaches its peak in the beginning grades.