My sister told me all … was said at the meeting.

Analyze the question The sentence is: "My sister told me all ....... was said at the meeting." We need the word that correctly links "all" to the clause "was said at the meeting."

Explain the concept After indefinite pronouns such as all, everything, something, anything, nothing, none, little, much, we normally use the relative pronoun that. We do not use which or what here.

• what already means "the thing(s) that," so it cannot follow "all" because it would repeat the idea. "All what was said" is wrong.
• which refers to things, but it is not used after all. It is used after a specific noun, usually in a non-restrictive clause.
• who refers to people, but the thing being talked about here (what was said) is not a person.

Step-by-step solution

1. The antecedent is "all," an indefinite pronoun meaning "everything."
2. The relative clause needs a subject for "was said," so we need a relative pronoun that serves as the subject.
3. After "all," the correct relative pronoun is that.
4. Check: "My sister told me all that was said at the meeting." This is grammatically correct and natural.

Option B ("what") would give "all what was said," which is incorrect. "My sister told me what was said at the meeting" would be correct, but only without the word "all."

Correct answer: A. that

Tip: Remember the pattern all / everything / nothing / something / anything + that. If you see one of these words before a blank, pick that. Also, never put all and what together.