What event aided the further development of the airplane? the development of lighter steel increased industrial efforts for world war i political pressure advances made in automobiles advertising on the radio?

The one event that eventually had one of the major impacts on the influence of the advancement of airplanes was the World War I. To cite for example, starting in October 1911, Italy started to use aircraft for military purposes. Within a month, they realized that they could bomb enemy positions using airplanes, hence changing the direction of the airplane industry forever.

Therefore the answer among the choice is:

 increased industrial efforts for world war i

the mongolian invasion of china and central asia resulted in a disruption of the silk road as the chinese garrisons lost support from the chinese kingdoms which fell under the mongols. however, as the mongols established a formal dynasty in china, the successors of genghis khan restored the garrisons along the silk road allowing the safe travel caravans again.

i think its either b or c

explanation: