In this English grammar error-spotting question, identify which part of the sentence contains the mistake: "I was shocked (A) to see how much my grand mother had aged (B) since the last time we visited her. (C) No Error. (D)". Choose the option that marks the incorrect segment or select 'No Error' if the sentence is fully correct.

Introduction / Context:
This question tests both grammar and standard spelling in English. The sentence describes an emotional reaction to the ageing of a close relative. While the grammar and tense usage are largely correct, there is a common spelling error involving a family relationship term. Your task is to identify which part of the sentence contains that error.

Given Data / Assumptions:

• Sentence: "I was shocked to see how much my grand mother had aged since the last time we visited her."
• Part A: "I was shocked"
• Part B: "to see how much my grand mother had aged"
• Part C: "since the last time we visited her."
• Part D: indicates "No Error".
• The intended family term is the standard English word for the mother of one's parent.

Concept / Approach:
While many error-spotting questions focus purely on grammar, exams also test spelling of commonly used words. The correct single word for the mother of one's father or mother is "grandmother", not "grand mother". English treats "grandmother" as one compound noun. The rest of the sentence uses appropriate tenses: "was shocked" (past simple), "had aged" (past perfect), and "visited" (past simple) in a temporal clause with "since". Therefore, the only problem is the incorrect splitting of "grandmother" into two words in Part B.

Step-by-Step Solution:
Step 1: Check Part A: "I was shocked". This is grammatically correct; it uses simple past to describe the reaction. Step 2: Examine Part B: "to see how much my grand mother had aged". The structure "to see how much ... had aged" is correct for expressing surprise at the degree of ageing. Step 3: Notice the spelling: "grand mother". The standard spelling is the single word "grandmother", not two separate words. Step 4: Check Part C: "since the last time we visited her." This is a correct time clause, using "since" with a reference point in the past. Step 5: Thus, only Part B contains an error, and that error is orthographic rather than structural.

Verification / Alternative check:
Rewrite the sentence correctly: "I was shocked to see how much my grandmother had aged since the last time we visited her." Now the entire sentence reads naturally and follows standard spelling. Dictionaries and school textbooks always treat "grandmother" as one word; similarly, "grandfather", "granddaughter", and "grandson" are also written as single words in modern English. This confirms that "grand mother" is not an accepted spelling in formal contexts.

Why Other Options Are Wrong:

• Part A: The phrase "I was shocked" is grammatically correct and appropriate for the context.
• Part C: The clause "since the last time we visited her" is correctly constructed and uses the past simple after "since" to mark a reference visit.
• Part D (No Error): Cannot be chosen because there is a clear spelling mistake in Part B.
• Error in more than one part: Not applicable, as only the spelling in Part B needs correction.

Common Pitfalls:
Students sometimes treat compound family terms inconsistently, writing "grand mother", "grand father", or "grand daughter" as two words. While older texts sometimes used hyphens, standard modern usage combines them into one word: "grandmother", "grandfather", and "granddaughter". In competitive exams, spelling errors with such frequently used words are penalised, so it is important to internalise the correct forms.

Final Answer:
The erroneous segment is Part B: "to see how much my grand mother had aged"; "grand mother" should be written as "grandmother".