This Surah is Makki. The Makki Surahs were revealed to establish the Belief (doctrine). The belief that Allah (swt) is The One and Only Who and the belief in the Angels, Divine Books, Prophets, Day of Judgement and the Divine Decree.
Surah An-Naba’ speaks about the Day of Resurrection, a matter which is very circumstantial and important. In Surah Al-Mursalat, Allah (swt) says:
﴾إِنَّمَا تُوعَدُونَ لَوَاقِعٌ ﴿
(Indeed, what you are promised is to occur). (Al-Mursalat: 6)
﴾ وَمَا أَدْرَاكَ مَا يَوْمُ الْفَصْلِ﴿
(And what can make you know what is the Day of Judgement?). (Al-Mursalat: 14)
Therefore, the subjects in Surah An-Naba’ is connected to what is found in the Surah before it.