Post-Traumatic Stress Disorder (PTSD) and Acute Stress Disorder Follow the Experience

Post-traumatic stress disorder (PTSD) and acute stress disorder follow the experience of a severe and traumatic life event to which an individual reacted with extreme fear, horror, or helplessness. Acute stress disorder is similar to PTSD, but has a more specific timeline. Which of the following describes that timeline?

A) Onset of symptoms within one month, symptoms last one month
B) Onset of symptoms within one month, symptoms last two months
C) Onset of symptoms within two months, symptoms last one month
D) Onset of symptoms within two months, symptoms last two months