Which of the following is illegal when trying to influence a coal mine worker regarding their statements to an inspector?

The option identified as correct involves actions that are expressly prohibited when attempting to sway a coal mine worker’s statements to an inspector. Threatening dismissal undermines the integrity of the inspection process by creating an environment of fear and intimidation. It compromises the worker's ability to provide honest and accurate information, which is crucial for maintaining safety and compliance in the mining industry.

In contrast, encouraging a worker to answer truthfully aligns with ethical practices and supports a transparent process. Promising a raise for cooperation may not be acceptable either, as it creates a transactional obligation that could affect the worker's willingness to provide an honest account, but it does not carry the same immediate threat as a dismissal. Offering training opportunities is generally seen as a positive action and shouldn’t be regarded as a coercive strategy.

Thus, actions that involve intimidation or coercion, such as threatening job security, are deemed illegal as they violate principles of fair practice and can severely impact the safety regulations laid down by mining law in Queensland.