In the context of modern Middle Eastern history, which event involved a bomb being smuggled into a guesthouse in Tehran several months prior to its detonation, resulting in the death of a Hamas leader?
A) The assassination of Ahmad Jibril in 2020.
B) The bombing of the Tehran guesthouse in 2018.
C) The killing of Baha Abu al-Ata in 2019.
D) The death of Imad Mughniyeh in 2008.