Echo Questions in Technical English

An echo question repeats the original statement (with the subject pronoun adjusted) using rising intonation instead of subject-auxiliary inversion, to express surprise or request confirmation. Option B is correct: "You're rolling back the entire release?" — it echoes the statement almost verbatim, only changing "we're" to "you're", and relies on question intonation (shown by the question mark) rather than inversion. Option A uses a wh-echo question ("rolling back what?"), which is a different, valid echo-question type used when only part of the information is in doubt — but it does not confirm the specific fact stated ("the entire release"); it asks the speaker to repeat that part. Option C is a tag question, a different structure entirely. Option D incorrectly inserts "did" while keeping the -ing form, producing an ungrammatical hybrid.

A wh-echo question keeps the statement's original word order (no inversion) and simply replaces the surprising element with a wh-word, placed where that element occurred — here, at the end, since "for eight months" was at the end of the original statement. Option A is correct: "It has been in production for how long?" mirrors the statement structure, with "how long" replacing "eight months" in its original position, signaled as a question by intonation/context. Option B is a standard, fully-inverted wh-question ("How long has it been...") — grammatical, but not an echo question; it does not preserve the statement's original word order. Option C incorrectly fronts "for how long" while keeping statement word order, which is not how English forms this echo structure. Option D uses "what" instead of "how long", which does not match the type of information (a duration) being questioned.

Option A is the most natural full echo question in this context — it repeats the entire statement with rising intonation, expressing genuine surprise while still confirming exactly what was said. Option B is a standard yes/no question with subject-auxiliary inversion — grammatical and usable, but it is not an echo question; it does not have the same rhetorical effect of directly mirroring the surprising statement back. Option C ("You did what?") is a valid, very informal echo question but it questions the entire action generically rather than confirming the specific detail already given — appropriate for extreme disbelief, but less precise/professional than option A for a stand-up. Option D scrambles normal word order and is ungrammatical.

Option A correctly describes the register distinction: echo questions (statement word order + question intonation) are typically used in spontaneous spoken reactions — expressing surprise, alarm, or seeking immediate confirmation — and feel more informal and emotionally charged. Fully inverted questions ("Was the API key committed...?") are more neutral and are the default choice for formal spoken or written questions, such as in an incident report follow-up. Option B is incorrect because register does differ, even though both are grammatical. Option C is incorrect — the echo question is a complete, grammatically valid sentence in spoken English, not a fragment. Option D is incorrect — echo questions are a spoken/conversational phenomenon primarily, essentially never used in formal written documentation, the opposite of what the option claims.

Option A correctly forms a wh-echo question by keeping the statement's word order intact ("The client wants the feature by...") and substituting the surprising element ("Friday") with the appropriate wh-word ("when") in its original position at the end. This directly signals which piece of information the speaker finds hard to believe. Option B breaks statement word order without applying the subject-auxiliary inversion required for a standard question, making it ungrammatical. Option C is a grammatically correct standard inverted wh-question, but — like earlier examples — it is not an echo question, since it does not mirror the original statement's structure. Option D substitutes "what" for "the feature" instead of "Friday" — the wrong element for expressing disbelief specifically about the deadline.