Coolest doubt in Mahabharat

In some remote village of India, one masterji is teaching the Mahabharat
katha to class 6 students.

He is at the krishnajanma' part of it. Masterji: "Kansa heard the
akashwani that his sister's 8th child is going to kill him.

He was furious. He ordered to put vasudev n devki behind the bars.

First son is born, and kansa kills him by poisoning...

Second one is born n kansa throws him off the mountain peak.

Third one is born." Now Ramu, who is smartest of the
lot, puts up his hand.

Masterji, I have a doubt (sounding nervous n confused)

Masterji: "Ramu bete, whole India does not have doubt in
Mahabharata

then how come u have one?"

Ramu : Masterji, if Kansa knew that Devaki's 8th child
was going to kill him,

WHY THE HELL DID HE PUT VASUDEV AND DEVAKI IN THE SAME
CELL ?

Masterji fainted.........................