The correct answer is option 1, which includes options 1, 2, and 4.

1. Equatorial calms: The doldrums are areas near the equator where there is little to no wind. This creates a calm and stagnant atmosphere, leading to a lack of wind and often called equatorial calms.

2. Calm and light winds: The doldrums are known for their calm and light winds. The absence of strong winds in this region makes it difficult for ships to navigate through.

3. Roaring forties: This option is incorrect. The roaring forties are strong westerly winds found in the southern hemisphere between latitudes 40° and 50°S, not in the doldrums.

4. Variable both in position and in extent: The doldrums are not fixed in one specific location. They can shift and expand depending on various atmospheric conditions. Therefore, their position and extent can vary.

So, the correct answer is option 1, which includes the accurate statements about the doldrums.