A restrictive clause is not preceded by a comma and it is making a clear distinction about the subject in the sentence.
That is the reason why, the only sentence that includes a restrictive clause is the third one, in order: "The ceramic cups Birgit bought at the garage sale are al chipped."
The answer to your question would be that the sentence that includes a restrictive clause is the following one: The ceramic cups Birgit bought at the garage sale are all chipped.
The sentence above contains a reduced relative clause because it does not contain the relative pronoun (a). What is more, it is restrictive because it adds essential information to the sentence; it helps identify the noun it modifies (the ceramic cups Birgit).
a) The ceramic cups Birgit which were bought at the garage sale are all chipped.
Jefferson believes that all men are free and have the right
to make their own decisions. This was
how Jefferson gave weight to his views when he helped create the Declaration of
Independence which inspired the colonies to be free of British rule in 1776.
