In the following sentence, identify the part that contains a grammatical error, or choose No error if the sentence is correct: No beggar who comes to our doors goes back empty handed.

Introduction / Context:
This is another error spotting question that checks your understanding of number agreement and idiomatic usage in English. The sentence describes a situation where no beggar who comes to a family's house goes away without receiving something. The focus is on the phrase to our doors, which looks acceptable at a glance but is slightly incorrect in standard idiomatic English. Such subtle plural versus singular issues are common in grammar sections of competitive exams.

Given Data / Assumptions:

• Complete sentence: No beggar who comes to our doors goes back empty handed.
• Part A: No beggar who comes.
• Part B: to our doors.
• Part C: goes back empty handed.
• Part D: No error.
• We must choose the segment that contains the error.

Concept / Approach:
The phrase no beggar who comes refers to one beggar at a time. In English, when talking about visitors coming to a house, the usual idiomatic expression is to our door, not to our doors, even if more than one family member lives there. The relative clause who comes is singular, and the idea is that each beggar comes to the entrance of the house, that is, the door. Using doors makes the phrase sound awkward and less idiomatic. Therefore, Part B is incorrect and should be changed to to our door.

Step-by-Step Solution:
Step 1: Read the full sentence to understand the meaning: no beggar leaves their house without some help. Step 2: Examine Part A: No beggar who comes. This correctly introduces a singular subject and a relative clause. Step 3: Examine Part B: to our doors. Here the plural doors does not match the usual idiom of someone coming to the door of a house. Step 4: Examine Part C: goes back empty handed, which is grammatically fine and conveys that the beggar does not leave without receiving anything. Step 5: Conclude that Part B contains the number and idiom error; it should read to our door.

Verification / Alternative check:
Rewrite the sentence using the corrected phrase: No beggar who comes to our door goes back empty handed. This now sounds natural and idiomatic. You would commonly hear people say come to my door or knock at the door when referring to a single entrance, even if the house has several doors physically. In exam grammar, such conventional usage is preferred. Therefore, the only necessary change is in Part B, confirming it as the error segment.

Why Other Options Are Wrong:

• No beggar who comes: This part is grammatically correct, with no issue in subject or verb.
• goes back empty handed.: This part correctly uses the singular verb goes with singular subject beggar and the phrase empty handed is a standard expression.
• No error: This would be chosen only if there were no mistakes, but the plural doors proves that an error exists.

Common Pitfalls:
Students sometimes overlook subtle idiomatic points and accept phrases that are grammatically possible but not natural English. Another pitfall is to focus only on tense or agreement and ignore number issues inside prepositional phrases. To handle such questions effectively, pay attention to fixed expressions like come to the door, on the way home, at school and so on. These expressions often appear in exam questions, and knowing them well saves time and reduces confusion.

Final Answer:
The part containing the error is to our doors, that is, option B, which should be corrected to to our door in standard idiomatic English.