Sentence Correction (SC) | Re: The English physician Edward Jenner found that if experimental subject

hiameyaprabhu

I am not expert,but let me share my two cents.

By default,which andthat
are noun modifiers and shall obey touch rule,
simply meaning the noun they modify must be placed as close as possible.

You may check an article byGMATNinja here

There are few exceptions as mentioned in above post. Do try to search for another
noun for which / that to modifyonly when closest noun does not make sense as in few OG examples in above post.

Coming to your query, I do not see a reason for
...

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