A、provided by terrorists B、stolen from the military C、made according to the methods shown in Internet D、made in his lab C

A key component in the explosives used in last week’ s London bombings is triacetone triperoxide (TATP), a U.S. law enforcement official tells U.S. News. TATP is a sophisticated or "high yield" explosive that’ s easily mixed at home with recipes available on the Internet.
  It was used by suicide bombers in Israel and chosen as a detonator in 2001 by would-be shoe bomber Richard Reid. Reid, who attempted to bomb a plane as it crossed the Aflamic Ocean, has claimed he used an Internet recipe to make his sneaker bomb. The ingredients in TATP — hydrogen peroxide obtained from local pharmacies, the paint thinner acetone, and a little hydrochloric or sulphuric acid-- can be mixed to manufacture TATP, which packs the same punch as plastic explosives such as RDX. TATP, used by terrorists in the Middle East and elsewhere, is considered so unstable that it can be set off by clapping one’ s hands to detonate it or stomping on it with one’ s foot and usually is used with other ingredients as a booster or detonator component.