Find the color of the cards?

Question

Four persons A,B,C,Dare playing cards.Each person has one card, laid down on table ,which has two different colours on either side.The colours visible on the table are red,green,red and blue.
they see the colour on reverse side and give folling comments.
A:yellowor green
B:neither blue nor green
C:blue or yellow
D:blue or yellow
Given that out of 4 people 2 always lie .find out colours on the cards of each.

Answer 1

A. Yellow
B. Red
C. Yellow
D. Blue

Answer 2

green

Answer 3

b