C. The Rubbish was thrown away
Feedback An indefinite or vague pronoun (such as they, we) which is used in the active voice is avoided in passive. There is no need to put the agent with by till the time it doesn’t alter the sense of the sentence. Not being a past continuous sentence, being cannot be used. Also, from past tense the sentence cannot be changed to future as that will change the meaning. Keeping these conditions in mind, the most appropriate choice would be option (c)