Out of 4 fruits, any 3 are chosen by 4 families.So the combinations are
Apple - A Cherries - C Banana - B Grapes - G
By 2nd condition, Miller family uses either i)ACB or ii)ACG
Now we have Robin, Mandy and Miller who uses apples (ACB,ACG,GAB)
while Miller and Mandy both uses A and C. That leaves GAB for Robin.
By 3rd condition Flure uses either C or G. So if we leave out the terms containing both C and G, we are left with ACB and GAB
Now, for the time being let's suppose Robin is not a Flure.
So ACB is taken by Flure.
So ACG has to be Miller and that leaves BCG to be Clark. So we get Robin - Jacob(GAB).
By 4th and 2nd conditions Erica and Mandy belong to the first two. That leaves Stacy - Clark(BCG).
By 2nd condition Mandy is not a Miller, so we get Mandy - Flure(ACB) and that leaves Erica - Miller(ACG).