try like below:
var Color = FROM P IN ProductMaster
JOIN Co IN
(
FROM C IN ProductInfoView SELECT new {Color=C.Field<string>("Color"), ProducID=C.Field<int>("ProductID")}
)
ON Co.ProducTID Equals P.Field<int>("ProducID)
WHERE P.Field<int>("ProductID")==956
SELECT Co.Color;
hope it works.