Explanation:

- Option 1: "in this apartment"

- This part is grammatically correct. It states the location where they have lived.

- Option 2: "since ten years"

- This part contains the error. The correct phrase should be "for ten years" instead of "since ten years". "Since" is used with specific starting points in time, like a year or date, whereas "for" is used for durations of time.

- Option 3: No error

- This option is incorrect because there is an error in the sentence as explained in Option 2.

- Option 4: "They have lived"

- This part of the sentence is correct. It uses the present perfect tense correctly to describe an action that began in the past and continues to the present.

- Correct Answer: Option 2, "since ten years"