Error Spotting (Grammar) — choose the part that contains a grammatical error. If the sentence is correct, choose ‘‘No error.’’ Complete sentence: He is a mason who built my house.

Introduction / Context:
This item checks relative clause usage with appropriate tense. The sentence describes a person’s occupation (present) and a specific past action that the same person performed.

Given Data / Assumptions:

• Main clause: ‘‘He is a mason’’ (present state/occupation).
• Relative clause: ‘‘who built my house’’ (completed past action).

Concept / Approach:
It is acceptable to use a past-tense relative clause to refer to a specific action done by someone whose present occupation is being stated. No change of tense is needed.

Step-by-Step Check:
Subject–complement structure is correct.Relative pronoun ‘‘who’’ correctly refers to ‘‘a mason.’’Past simple ‘‘built’’ is suitable for a finished action.

Why Other Options Are Wrong:
They each represent grammatical segments. No alteration improves the sentence.

Common Pitfalls:
Overcorrecting by forcing present perfect in the relative clause; it is unnecessary here.

Final Answer:
No error.