PUZZLE 153 Truth, Lies and a Box of Balls

Four people are talking next to a box with a four-by-four grid.
Let's call them A, B, C and D.
A says, 'There are two balls in each vertical line.'
B says, 'There is one ball in each horizontal line.'
C says, 'There's a ball in each of the four corners.'
D says, 'The only person lying here is A.'
Two of the four perple are lying.
Each slot can take one ball, so how many balls are in the box in total?

Hint 1

Two of the four people are lying, but D says, 'The only person lying here is A.'
That means D must be lying.

Hint 2

Which stories out of A, B and C tie in with each other?
Try assuming one person is correct and see if what they say matches up with anyone else.
Whoever doesn't match up must be lying.

Hint 3

Continuing on from hint two...
The only stories that tie in with each other are A's and C's.
That means B must be lying.

Super Hint

A and C are telling the truth.
So if a ball is placed in each corner, and there are two balls in each vertical line, how many balls will there be in total?

Answer for 'Truth, Lies and a Box of Balls'

The answer is '8'.