Error Spotting – Identify the part of the sentence that contains a grammatical error (choose exactly one; select “No error” if the sentence is fully correct). Sentence: A) If you would have B) gone to his house C) before 10 a.m., you would have D) got his autograph.

Introduction:
This sentence examines the correct form of a third-conditional (counterfactual past) structure. The if-clause must use past perfect, not "would have."

Given Data / Assumptions:

• Intended meaning: a missed opportunity in the past.
• Main clause already uses "would have" → appropriate for third conditional.
• If-clause incorrectly uses "would have" instead of past perfect.

Concept / Approach:
Third conditional pattern: If + past perfect, would have + past participle. Therefore: "If you had gone ..., you would have got/gotten ...".

Step-by-Step Solution:
1) Identify conditional type: counterfactual past.2) Fix if-clause: "If you had gone."3) Keep main clause: "you would have got his autograph."4) Corrected sentence: "If you had gone to his house before 10 a.m., you would have got his autograph."

Verification / Alternative check:
Swap clauses: "You would have got his autograph if you had gone ..." confirms the pattern.

Why Other Options Are Wrong:

• B: Past participle "gone" is correct after "had" (once fixed).
• C: Punctuation/time phrase is fine; main clause form is correct.
• D: "got" is acceptable in many dialects; "gotten" is also fine in American usage.

Common Pitfalls:
Using "would have" in both halves; mixing condition types.

Final Answer:
Option A