Maria is a well-known celebrity. at an award ceremony, she was interviewed by journalists and reporters. even though she had no time to prepare, she responded their questions with witty statements. in this scenario, maria's interview is an example of a(n)

This is an example of an impromptu speech.
Impromptu basically means to wing something, to improvise. Maria didn't have time to prepare for the interview, she didn't know the questions in advance, so she had to improvise when it came to her answers. However, she managed to give witty statements regardless of the fact that she didn't prepare them beforehand. 

Because global warming is occurring and there’s no ice for the polar bears to live on.