Q: Craft one incorrect answer. In doing so, try to use words from the context as much as possible, or by using similar words used in the correct answer. DO NOT craft nonsensical or off-topic incorrect answers, such that the incorrect answers can be directly excluded without reasoning according to the context. Try to make your responses similar to the given correct answer. To this end, try to keep both the length and the style as similar as possible between the correct and the incorrect answer. To make your incorrect answers more difficult, try to incorporate words from context. To avoid being predictable or repetitive, try to add more variations and complexity.
Context: Also , no souvenirs of the crime , such as newspaper clippings , were found in his possession as commonly seen in serial murder cases . What 's more , the FBI could not place Ivins at the crime scene with evidence , such as gas station or other receipts , at the time the letters were mailed in September and October 2001 . While acknowledging the circumstantial nature of their case against Ivins , prosecutors argue they 're confident they would have been able to prove his guilt " beyond a reasonable doubt " in court .
Question: What 's a possible reason there were no souveneirs of the crime found in his possession ?
Correct Answer: None of the above choices .
A:
Because letters were mailed in September and October 2001 .