I will go with 6 i.e option B.
I course contain 3 varieties
II course contain 4 varieties
III course contain 3 varieties
Suppose there are p beverages .
We have to order a dish for atleat two courses and one beverage.
Case 1 Exactly 2 courses and one beverage
These 2 courses again could be from
I ,II or II, III or I, III
So this will be 3C1x4C1xpC1 + 4C1x3C1xpC1 + 3C1x3C1xpC1
i.e 12p+12p+9p = 33p
Case 2: Exactly 3 courses and one beverage.
This will be 3C1x4C1x3C1xpC1 = 36p
So minimum 6 beverages must be offered
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