Identifying Oxymoron in Literature

In a literary context, both paradox and oxymoron serve important roles in illuminating contrasts and complexities in human experience. A paradox is a statement that seems self-contradictory but may nevertheless reveal an underlying truth. An oxymoron, on the other hand, is a figure of speech that combines seemingly contradictory terms to create a new meaning or insight.

Consider the following sentences:

1) 'The deafening silence hung heavily in the air.'

2) 'Love is a battlefield.'

3) 'She was both a friend and an enemy.'

4) 'His excitement was palpable, yet his heart felt heavy.'

5) 'The only thing we have to fear is fear itself.'

Which of these sentences exemplifies the use of an oxymoron?