Look at the poster

the contrast of the white print on the red background is

most designed to

inspire audiences

capture attention

encourage action

promote careers

don't miss

your great

opportunity..

Capture Attention

Explanation:

Red is mostly used to capture attention as it stands out very prominently from other colours. It is a marketing tool to use dark colours especially red in advertisements and commercials.

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).