Choose the correct form of the verb. He ___ several times. The reason is a lot of dust in the attic.

The sentence describes an action that has happened multiple times in the past and is likely to continue or has a present result (the reason for coughing). The present perfect continuous tense, 'has been coughing', best fits this context, indicating a continuous action with a present relevance. The phrase 'several times' suggests repetition, and the reason 'a lot of dust' implies an ongoing or recurring cause. Therefore, 'has been coughing' is the most appropriate choice to convey that the coughing has been happening repeatedly due to the dust and is the reason for the current situation.

The correct answer is: has been coughing