A can do 1/2 of a piece of work in 5 days, B can do 3/5 of the same work in 9 days, and C can do 2/3 of that work in 8 days. In how many days can all of them together do the work?

Options:

• A: 3 days
• B: 4 days
• C: 4.5 days
• D: 5 days

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