What is the dependent clause and subordinating conjunction or relative pronoun?

[Simonah]

Dear teachers,

What is the dependent clause and subordinating conjunction or relative pronoun in this sentence?

Hikers who attemp to walk the whole length of the trail have to put their lives on hold for several months.

Many thanks
Simonah

[Mister Micawber]

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'Who' is the subordinator and is the head of the dependent clause.
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Native English teacher at Mister Micawber's

[El_Profe_x]

The clause that begins with "who" is an adjective clause. Though it technically can't stand alone, I think most of us wouldn't call it a dependent clause because it doesn't fit the criterion of beginning with a subordinating conjunction.