Complete the tech blogger's slightly dramatic review by selecting the correct clause.

My brand-new laptop, ________, is already making alarming clicking noises.

The correct answer is which I bought just yesterday.

The commas indicate that this is a non-defining relative clause (it adds extra information about the laptop). In non-defining relative clauses, we must use "which" for things.

You cannot use "that" after a comma in a relative clause, and you cannot omit the relative pronoun entirely if there are commas!