Explanation:

- A special resolution typically requires a majority of at least 75% of the valid votes cast.

- Out of 40 members present, 10 abstained, which means only 30 members voted.

- Of these 30, 6 votes were invalid, leaving 24 valid votes.

- To calculate the minimum votes needed for the special resolution:

$$

\text{{Minimum votes required}} = \lceil 0.75 \times 24 \rceil = 18

$$

- Hence, at least 18 valid votes are required in favor of the resolution to pass it.

- Option 1: 18 – This is the correct option.

- Option 2: 19 – While also more than 75%, it's not required to exceed in whole numbers.

- Option 3: 12 – This is too low, as it does not meet the 75% threshold.

- Option 4: 10 – This is similarly too low by the same logic.

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