Answer :
The demonstrative would be 'that'
Did you ask Laura if she wanted some of __that__ sandwich before you threw it away. It would be 'that' because it's asking about one things and referring to one thing in general not more than one: words sandwich and it hints the demonstrative.
But if the sentence said sandwiches and them instead then the demonstrative would be those.
Did you ask Laura if she wanted some of __that__ sandwich before you threw it away. It would be 'that' because it's asking about one things and referring to one thing in general not more than one: words sandwich and it hints the demonstrative.
But if the sentence said sandwiches and them instead then the demonstrative would be those.