The correct passive form of the given sentence is Susan was told to give up smoking by Uma.

The active voice of the sentence is Uma told Susan to give up smoking. This sentence is in the simple past tense, which is used to describe an action that happened in the past. The passive voice of the sentence is formed by putting the subject of the active sentence after the verb "to be" and the past participle of the main verb. In this case, the subject of the active sentence is "Susan" and the main verb is "tell." The past participle of "tell" is "told." So, the passive form of the sentence is Susan was told to give up smoking by Uma.

The other options are incorrect because:

• Susan is told to give up smoking by Uma. is in the present tense, but the action of Susan being told to give up smoking happened in the past.
• Susan has been told to give up smoking by Uma. is also in the present tense, but it implies that Susan has been told to give up smoking multiple times.
• Susan had been told to give up smoking by Uma. is in the past perfect tense, which is used to describe an action that happened in the past before another action happened. There is no other action mentioned in the sentence, so the past perfect tense is not appropriate.
• Susan told to give up smoking by Uma. is missing the verb "to be." The passive voice of the sentence must include the verb "to be."