Concept:Direct speech quotes the exact words spoken; indirect speech reports them with changes in tense, pronouns and modals.
Rule / Clue:The fixed idiom "if need be" does not change. The modal "would" in indirect speech back‑shifts from "will" in direct speech. The pronoun "he" refers to the advisor, so it becomes "I". Remove the conjunction "that" and add quotation marks.
Explanation:In the indirect sentence, "would" shows a past intention. To convert to direct speech, "would" reverts to "will" because the advisor originally stated a definite plan. The phrase "if need be" is a set subjunctive idiom and stays exactly the same. The pronoun "he" changes to the first‑person "I" because the advisor is speaking about himself. The conjunction "that" is dropped, and the words are enclosed in quotation marks with a capital letter at the start.
Option A matches all these rules correctly. Option B uses "needs" which is a less common variant and not the original phrasing. Option C changes "would" to "might", altering the meaning from definite intention to uncertainty. Option D has a missing opening quotation mark and keeps "would" instead of "will", which does not reverse the back‑shifting rule.
Answer:Option A: "If need be, I will intervene personally," said the advisor.