Which sentence sounds grammatically more correct?

[Pete671]

First is correct, but a bit terse,,,
Perhaps this helps to explain the reason why they are in jail,,,

[DiversityHire]

A, and good on you for working so hard on your English studies.

[Kaneki05]

1st even though everyone can understand it, and it makes perfect sense and English is just dumb lol

[Dazzler1983]

A - needs a comma after understand
B - should be that's not that.
I would say
" Now you know why he's in jail "

[virgin20]

First one.
Message me if you'd prefer!

[Yaaten]

"A" is definitely the correct one here.

[Lunatic1]

Definitely the first one

[DeeDeeDeVour]

"Now, you can understand why he's in jail."

[Jjpayne]

The first one

[Fukaroo]

First one is good.

[Gedaria]

,, A. ..

[IlluminatiExposed0]

A is correct.