The correct answer is: 1.1, 1.2, and 1.3
Explanation:
A decimal outline is an outline that uses notations such as 1.1, 1.2, and 1.3. In decimal outline, the notations have to be numbers, not letters or roman numerals.
Examples of Decimal Outline:
1. 1.1, 1.2, 1.3...
2. 2.1, 2.2, 2.2...
The other options, however, are either roman numerals or the letters.
Like:
Roman numerals: I, II, and III
Letters: A, B, and C; a, b, and c
Hence the correct answer is 1.1, 1.2, and 1.3.
