A developmental psychologistis investigating movement abnormalities as an early symptom of autism.Her research team is collecting data about crawling techniques from videotapes of 9-month-olds. To increase standardization of data collection, she should:___.
A) provide clear definitions of each crawling style with videotaped examples.
B) expand her study to include 12-month-olds.
C) collect data only on children with clinically significant crawling deficiencies.
D) have her research team collect data in person instead of by watching videotapes.