In Data Sufficiency for the Yes/No questions, if the options give a unique value which is No, can we consider it as an answer?

There are two types of data sufficiency questions:

1. YES/NO DS Questions:

In a Yes/No Data Sufficiency questions, statement(s) is sufficient if the answer is “always yes” or “always no” while a statement(s) is insufficient if the answer is "sometimes yes" and "sometimes no".


2. VALUE DS QUESTIONS:

When a DS question asks about the value of some variable, then the statement(s) is sufficient ONLY if you can get the single numerical value of this variable.

Strategies and Tactics for DS Section

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C-Trap Questions
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Another Manhattan GMAT blog on C-Trap.
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For more check Ultimate GMAT Quantitative Megathread

Hope it helps.
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