General rule 1: There should be no empty paragraphs.
2.2 Why you should press Enter only once to end a paragraph

General rule 2: Use Styles to format your text.
3. Using Styles to Format Text

General rule 3: Set up your numbering by linking it to styles.
How to create numbered headings or outline numbering in Ribbon Versions of Word by Shauna Kelly

Specific to your question:
Set up at least three styles.
One for your numbered questions with space before formatting. This should have the formatting as part of the style of keep with next. It should be set to be followed by a subsidiary lettered style for your first three choices. That style should also be set to keep with next. A third style should be based on the second style. It should be lettered but not be set for keep with next. Further, the style for following paragraph should be set for your first style.

The formatting for the question is automatically followed by that for the first three answers. When the last answer comes up, you will need tApo apply a style manually for the last answer. When you hit Enter at the end of that paragraph, you will automatically start the next question.

This makes creating such a set of numbered lists easy. Applying the styles to text in a document after the fact will be a bit more difficult. Nevertheless, applying styles to text is still far easier than applying direct formatting.