93, 309, 434, 498, 521, 533

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Question: 93, 309, 434, 498, 521, 533
[A].

309

[B].

434

[C].

498

[D].

521

Answer: Option D

Explanation:

The correct pattern is + 63, + 53, + 43, + 33, …..

So, 521 is wrong and must be replaced by (498 + 33) i.e. 525.