How can the choice to present a story through the medium of radio most
affect an audience's perception of it?

the following key ideas correctly express the key sentence.

restate key idea: most people can learn to swim in ten short lessons.

restate key idea: the majority of water-accident victims require mouth-to-mouth breathing.

restate key idea: an empty, tightly closed gallon jug will support a tired swimmer.  

restate key idea: first aid is to prevent accidents as well as assist in rescue.

explanation: the key idea needs to have the same topic as the key sentence (drowning and safety).

there is 2 main differences, basically which are the users and the market. the other difference is the kind of content

people who use tik tok are mainly people from east asia, kind of like the app douyin. musically, on the other hand, are used by people from america or european countries.

while tik tok videos show things like daily life videos, comedy, or just funny videos, musically are like people mimicking songs with their own actions, 'imitate' singers and video clips.

hope this !