What is a question mark?
A question mark is a form of punctuation used at the end of a sentence to denote uncertainty. A question mark looks like this: ?
Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request.
### Instruction: What is a question mark?
### Input: 
### Response: A question mark is a form of punctuation used at the end of a sentence to denote uncertainty. A question mark looks like this: ?