In dynamic programming, what is the key difference between a 0/1 knapsack and an unbounded knapsack?

• A. 0/1 knapsack: each item can be chosen at most once; unbounded knapsack: items can be chosen unlimited times.
• B. 0/1 knapsack allows unlimited repeats; unbounded allows at most once.
• C. 0/1 knapsack uses greedy; unbounded uses DP.
• D. They are identical except for capacity.

Answer: (A)