Change the given sentence of active voice into passive voice. Select the appropriate option. The Prime-minister was giving the speech.

The correct option is: The speech was being given the Prime-minister.

Let us break down the step-by-step grammatical rules to understand why this option is correct:
1. Identify the tense of the active voice sentence: The sentence "The Prime-minister was giving the speech" uses the past continuous tense ("was giving").
2. Apply the passive voice rule for continuous tenses: To convert a sentence in the past continuous tense (Subject + was/were + V-ing + Object) to passive voice, we follow the structure:
Object + was/were + being + past participle of verb (V3) + [by + Subject].
3. Identify sentence components:
- Subject: The Prime-minister
- Verb: was giving (past continuous of 'give')
- Object: The speech
4. Convert:
- "The speech" becomes the new subject.
- "was giving" is transformed to "was being given" (since 'speech' is singular).
- Applying this structure matches the provided correct choice: "The speech was being given the Prime-minister."