The single most misunderstood NISM rule. Here it is series-wise:
With 4 options and a 25% penalty, a pure blind guess has an expected value of exactly zero — you gain nothing on average. But eliminate one option and guessing turns positive; eliminate two and it is clearly worth attempting. That is the rule to drill in mocks: never guess blind, always guess after elimination.
Candidates who move from V-A (no penalty) to X-A or XV often carry the "attempt everything" habit with them — and lose 5–10 marks to it. Practising on a mock with the same negative-marking engine breaks that habit before the real exam does.
No. Series V-A has zero negative marking — attempt every question.
25% of the marks assigned to that question. For a 1-mark MCQ that is 0.25; for a 2-mark caselet question it is 0.5.
Only after eliminating at least one option — ideally two. A blind 4-option guess with a 25% penalty has zero expected value.