How Should We Interpret the Correlation Between Schizophrenia and Birth

 How should we interpret the correlation between schizophrenia and birth complications?

A) Birth complications clearly cause schizophrenia in the mother.
B) Birth complications clearly lead to the later development of schizophrenia in the child.
C) Infants who will later develop schizophrenia are difficult to carry and deliver.
D) Birth complications may trigger schizophrenia, or an infant who is vulnerable to schizophrenia may be difficult to carry and deliver, or both.