Usage of That

Hi,

Prep Phrases always start with prepositions. Here the preposition is "in". So, only 'in individuals' is a prep phrase. Here "that" jumps the prep phrase to refer to the noun "responses".

that always refers to the noun it's placed next to. But in this case there is a noun phrase - "responses (noun) + in individuals (noun modifier)". "that" can jump the noun modifier phrase to refer to noun (responses). The usage is okay as long as :

- There is no ambiguity as 'that' cannot refer to individuals (we need 'who' to refer to individuals'. So this usage is considered okay.
- Whatever comes between 'that' and its referent noun is a noun modifier. In this case 'in individuals' is a noun modifier.

I've seen a couple official questions in which there is a verb between noun and 'that'. It was in the correct answer choice. Keep these exceptions in mind, and use them only if you are able to confidently mark other 4 options wrong. Between Rule and Exception, always go with the rule - that must be placed next to the noun it modifies.

Hope this helps!