Read the description.
the critical point you want to make about a piece of literature
what is being deseribed?
the body of an essay
supporting details for an essay
the thesis statement of an essay
the conclusion of an essay

c is the answer : )

explanation:

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).