Explanation:

Let’s look at the options and what the law says:

- The Appropriate Government, when considering prohibition of contract labour, must consider if the work is:

- Incidental or necessary to the industry: This is relevant, as per Rule 25 of the CLRA Rules.

- Of a permanent nature: Relevant, as long-term and continuous work hints employment should not be contractual.

- Ordinarily done through regular workmen: Also relevant; if such work is done by regular employees elsewhere, contract labour may be improper.

- Of intermittent nature: NOT relevant; the law does not consider intermittent or casual nature when deciding prohibition.

The correct answer is:

- Option 4 – The work is of intermittent nature