Explanation:

- Obscene: This word means something offensive to moral principles or unsavory. It often involves content that is indecent or inappropriate.

- Option 1: Disgusting: This has a similar negative tone as obscene, referring to something highly unpleasant or repulsive. Not an antonym.

- Option 2: Desirous: This relates to having desires or wants. It's not directly related to morality or decency, so it's not an antonym of obscene.

- Option 3: Decent: This word means conforming to accepted moral standards or being appropriate and modest. It is the opposite of obscene.

- Option 4: Pornographic: This directly connects to obscene content, often used interchangeably. Not an antonym.

Your selection of "Option 3: Decent" is the correct antonym.