Modern firearms use the same principles as muzzleloading firearms. The ignition and burning of gunpowder create pressure. This pressure propels projectile(s) down the bore and out of the muzzle. The first modern firearms used black powder. Since about 1890, modern firearms are designed to use smokeless gunpowder. Smokeless gunpowder creates greater pressures and should not be used in firearms designed for black powder. Watch what happens when the trigger is squeezed on this bolt action rifle.
Amongst the options given, the possible answer would be "that Sayuri's intelligence is way beyond her years". A critical person can arrive at this answer because the situation stated that Sayuri had habits that differ from other children. Those extraordinary habits can be connected to the child's intellectual level. Kids that are more intelligent than the others will tend to display habits that are out of the ordinary.
Try your hardest to solve the problem in the situation