Question

which sentence contains a restrictive clause?
the dance performance, which took place on a bridge, was quite interesting.
the tree that fell in our driveway will be removed on tuesday.
adela (who is a star athlete) has joined the debate club.
the cat—which has one green eye and one blue eye—likes to chase mice.

Explanation:

A restrictive clause is essential to identify the noun it modifies, uses "that" (for things) or "who" (for people) without commas/parentheses/dashes setting it apart. Non-restrictive clauses add extra, non-essential info and use commas, parentheses, or dashes with "which" or "who".

1. First sentence: "which took place on a bridge" is non-restrictive (set off by commas, extra info).
2. Second sentence: "that fell in our driveway" is restrictive—no separating punctuation, and it is necessary to specify which tree will be removed.
3. Third sentence: "(who is a star athlete)" is non-restrictive (set off by parentheses, extra info about Adela).
4. Fourth sentence: "which has one green eye and one blue eye" is non-restrictive (set off by em dashes, extra info about the cat).

Answer:

The tree that fell in our driveway will be removed on Tuesday.