Imām Ibn al-Jawzī (d. 597/1201) summarized the scholars' opinions in his book "Zād al-Masīr" as follows:

1.The meaning is: the example of those who disbelieve is like that of a flock of animals at which the shepherd yells. This is the view of al-Farrāʾ and Thaʿlab. They both said: The example appears to compare the disbelievers with the shepherd, but what is meant is that the example of the disbelievers is like the example of the cattle that do not comprehend what the shepherd says. To them it is mere sound, so if the shepherd says, "Graze" or "Drink," the animals do not understand his words. Similarly, the disbelievers respond to the Qurʾān and the prophet's warning in this way. The comparison is directed towards the shepherd, but the intended meaning is the flock, which is common in the Arabic language. For instance, they say, "So-and-so fears you like the fear of the lion," meaning like he fears the lion. 
2. The meaning is: the example of the disbelievers and our example in advising them is like that of the shepherd calling out and the sheep being called. The phrase "our example" is omitted for brevity since the context implies it. [Ibn Qutaybah, al-Zajjāj]
3. The meaning is: the example of the disbelievers calling upon the deities they worship is like that of the shepherd calling (sheep). [Ibn Zayd]

How does this āyah describe the state of the disbelievers?