Why Are the Taliban Reluctant to Increase Activities Outside of Afghanistan

Why are the Taliban reluctant to increase activities outside of Afghanistan?

A) They do not want to risk the security of their sanctuaries in Pakistan.
B) Their funding is running low and if they spread too thin they will be quickly destroyed.
C) The Taliban's only goal has ever been to create an Islamic caliphate in Afghanistan - other people are free to do what they want.
D) Doing so would likely lead to the discovery of their nuclear weapons in Syria.