Which of the following statements best describes a low explosive?

a. A substance that detonates with an accompanying blast.
b. A substance that deflagrate when unconfined, that is, through propagating energy comparatively slowly by burning.
c. Low explosives are typically formed using mercury fulminate, lead azide, and lead styphnate.
d. Low explosives are substances that are relatively insensitive to heat, mechanical shock, and friction.

B