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Let a1 , a2 ,... be in harmonic progress...

Let `a_1 , a_2 ,...` be in harmonic progression with `a_1 = 5` and `a_20 = 25`. The least positive integer n for which `a_n lt 0`

A

22

B

23

C

24

D

25

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The correct Answer is:
D
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