Jenny's Son Received His Mumps,measles,and Rubella Vaccine Approximately 6 Months

Jenny's son received his mumps,measles,and rubella vaccine approximately 6 months ago.Shortly after his 2nd birthday,she noted that he is showing many of the classic signs of autism.Her belief that the vaccine caused his autism is

A) an example of confirmation bias.
B) an example of hindsight bias.
C) an example of illusory correlation.
D) supported by several scientific studies.