whAt wAs thE CAusE oF thE Explosion
A．ChilDrEn plAying with FirE.
B．thE sEtting oFF oF FirEworks in A housE with ExplosivEs,
C．spArks From A FirEworks DisplAy FAlling on thE wArEhousE,
D．thE Firing oF A gun.