Answer:
1.Palm trees, which grow in warm climates, typically have large leaves.
2.My brother bought me a laptop that has a built-in camera.
4.The guide who led us through the canyon was very friendly.
Step-by-step explanation:
Relative clauses are those groups of words or phrases that have a subject and a verb in it but is unable to be deemed a full sentence on its own. It is also similar to a dependent clause and needs an independent clause to be a full, correct sentence and is also known as an "adjective clause" as they act as adjectives in the sentence.
Among the options given in the question, sentence 1, 2, and 4 contains relative clauses in them. In sentence 1, the relative clause "which grow in warm climates" describes/ modifies the noun "palm trees" while "that has a built-in camera" modifies "the laptop" in sentence 2. Likewise, sentence 4 contains the relative clause "who led us through the canyon" modifying the noun "the guide". They also contain a subject and a verb in each of them, thus making them relative clauses.
Thus, the correct answers are options 1, 2, and 4.