Consider the mixed knapsack problem, in which some items are divisible into arbitrarily small pieces $($as in the fractional knapsack algorithm$)$ but others are indivisible as in the $0-1$ knapsack problem $($that is$,$ you must take a full integer number of each such item$).$

Only one of the following three algorithm design paradigms can be used to ensure an optimal solution to the mixed knapsack problem. Which one would that be$?$

Question $3$ options:

Divide$-$and$-$conquer algorithm

Dynamic programming algorithm

Greedy algorithm