General category: Mathematics
Sub-category: Probability
Topic: counting techniques
Introduction:
The combination formula C(n,r) shows us the number of ways of picking r unordered outcomes from n possibilities. For n ≥ r ≥ 0, C(n,r) is given by the following formula:
Step-by-step explanation:We can use combinations and fundamental counting principles to answer this question.
Let us denote by "a", the number of selection of appetizers. This number can be calculated as follows:

Now, let us denote by "b", the number of selection of main courses. This number can be calculated as follows:

Finally, let us denote by "c", the number of selection of desserts. This number can be calculated as follows:

Now, applying the multiplication principle we get the desired number:

We can conclude that the correct answer is: