Explanation:

- Let's denote the time taken by Aditya, Harshit, and Vaibhav as A, H, and V days respectively.

- Given that Aditya takes thrice the time taken by Harshit and Vaibhav together: A = 3 * (H * V) / (H + V).

- It is also given that Harshit takes four times the time taken by Aditya and Vaibhav together: H = 4 * (A * V) / (A + V).

- All three together complete the job in 24 days, hence their combined rate is 1/24 work/day.

- Calculate individual rates: If Aditya alone can finish the job in 96 days, his work rate would be 1/96 work/day.

Given the options:

- Option 1, 90 days: Incorrect calculation for Aditya's time.

- Option 2, 96 days: This calculation fits all constraints when solved structurally and is the correct answer.

- Option 3, 100 days: Overestimates Aditya’s speed.

- Option 4, 80 days: Underestimates Aditya’s speed.

- Option 5, 110 days: Again overestimates Aditya’s speed.

Option 2, 96 days is correct.

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