The correct passive form of the given sentence is:

☀ The old lady in the street ought to have been saved.

Let's break down the options:

1. The old lady in the street ought to had been saved. (Incorrect) This option uses the incorrect past tense "ought to had been saved." The correct form should use "ought to have been saved."

2. The old lady in the street ought to have been save. (Incorrect) This option uses the incorrect base form "save" instead of the past participle "saved." The correct form should be "ought to have been saved."

3. The old lady in the street ought to have been saved. (Correct) This sentence correctly uses the passive voice and conveys the same meaning as the original sentence. It uses the correct form "ought to have been saved."

4. The old lady in the street ought to have saved. (Incorrect) This option changes the meaning of the original sentence. The original sentence suggests that "We" should have been the ones to help the old lady, but this option suggests that the old lady should have been the one to save something. The correct passive form should focus on the old lady being saved, not her doing the saving.