Tafsir Ibn Abbas: As-Saaffaat, Ayah 17

And our forefathers too?’ read aw ābā’unā indicating a supplement; or read a-wa-ābā’unā as an interrogative effecting the supplement with the wāw; so that what is being supplemented is either the inna together with its subject sc. a-inna la-mab‘ūthūna or the subject of the verb la-mab‘ūthūna in which case the interrogative hamza is a separator.