Which of the following is consistent with current literature about the relationship between obstetrical complications and Autism Spectrum Disorders (ASD)?
1) A Research is unclear whether obstetric complications are a true risk factor for ASD.
2) B Research proves there is a negative correlation between obstetrical complications and ASD.
3) C Research proves there is a positive correlation between obstetrical complications and ASD.
4) D Research strongly supports a positive relationship between obstetric complications and ASD.