Geometry

Question Analysis
This question requires the application of the combination formula for combinations with repetition.
The main focus is on correctly identifying the values of (number of cookie types) and (number of cookies to be bought) and then using the formula to calculate the number of combinations.

Key Concept Explanation
The formula is used when we want to choose items from types of items with repetition allowed, and the order of selection does not matter. Here, (types of cookies) and (number of cookies).

Step - by - Step Solution
First, calculate the factorials: