In this presentation we will only be discussing the elastic behavior of materials--what will happen when they stretched or squished non-destructively ("bowed"), and can still return to their original state afterwards. As for "bent" and "broken," we'll defer that discussion as our focus will be on avoiding permanent distortion or damage to materials.
Tension is when you stretch something, like these bridge suspension cables.
Compression is when you squish something, like the stones near the bottom of this stack.
For the different lengths of cable, which are stretched by the least amount (say, measured in cm) from their original lengths: the shorter lengths of cable, or the longer lengths of cable?
For the different cross-sectional area columns, which support the least amount of force: the narrower cross-sectional area columns, or the wider cross-sectional area columns?