The correct answer choice is 1, plural nouns. Answer choice 2 doesn't make sense, because you can use 'those' and 'these' with abstract nouns, such as in the phrase 'those ideas'. Answer choice 3 doesn't make sense, because you can use 'these' and 'those' with objects as well, such as in the sentence 'I want those apples'. Answer choice 4 doesn't make sense at all, because you wouldn't say 'those cat walked across the yard'. The only answer choice that makes sense is answer choice 1.
