Know the NOs: acing Prelims by reverse engineering

It is often more helpful to know the NOs. You don’t need to know the right answer to score +2: you need to eliminate the wrong ones. That lets you attempt extra questions and lowers the chance of getting an easy one wrong.

Endemic species

UPSC often asks which animal is found only in, or endemic to, a region. You can memorise every animal and its location, or you can know that only 15 to 20 animals are important and endemic to Indian locations.

Science and tech

There are two ways to study S&T. One: understand everything, then try to score. Two: accept that you need to remember it for one day, Prelims, and reproduce it. If you want marks and not a PhD in CRISPR-Cas9, keep it short and to the point. And in defence, space and missiles, know the country of origin: it eliminates at least two options in statement questions.

Five chapters of Ancient India that matter most

1. The Indus Valley Civilisation
2. The Vedic period
3. The Mauryan era, especially Ashoka
4. The Sangam period
5. Jainism and Buddhism (study them from culture)