Who is the author of the book titled "Colours of the Rainbow"?

Introduction / Context:
This is a books and authors question that focuses on "Colours of the Rainbow", a title used in competitive exam general knowledge sections. Knowing who wrote this book helps you handle questions on lesser known but frequently asked works. It also trains you to distinguish between different authors whose names may appear together in GK lists.

Given Data / Assumptions:

• The book title is "Colours of the Rainbow".
• Four authors are listed: A. V. Kamath, Anita Nayyar, Pritish Nandy, and Ranjit Biswas.
• Only one of these is credited with writing this book.
• The question is factual and requires no calculations.

Concept / Approach:
Standard GK references identify A. V. Kamath as the author of "Colours of the Rainbow". The other names in the options are also authors or public figures but are linked with different works and professional fields. By recalling this specific pairing of title and writer, you can mark the correct answer with confidence.

Step-by-Step Solution:
Step 1: Read the title "Colours of the Rainbow" and recognise that it is a book used in GK questions. Step 2: Go through the options and recall which author is associated with this specific title in exam oriented lists. Step 3: Remember that A. V. Kamath is credited as the author of "Colours of the Rainbow". Step 4: Choose A. V. Kamath as the correct option and eliminate the remaining names.

Verification / Alternative check:
You can verify this answer in competitive exam guides, GK compendiums, or lists of books and authors used by many coaching institutes. These references consistently match "Colours of the Rainbow" with A. V. Kamath. Consulting a couple of reliable sources is enough to confirm the authorship for long term recall.

Why Other Options Are Wrong:
Anita Nayyar is a media professional and author, but standard GK lists do not credit her with this specific title.
Pritish Nandy is a poet, journalist, and filmmaker, associated with different works and not primarily with "Colours of the Rainbow".
Ranjit Biswas is also a separate author and public figure, but he is not identified as the writer of this book in standard references.

Common Pitfalls:
Because all the options appear to be plausible names, some students guess randomly or pick the one they have heard most often in media. Others may confuse this title with children's books or poetry anthologies with similar sounding names. To avoid such errors, build and revise a dedicated list of frequently asked books and authors, including "Colours of the Rainbow" by A. V. Kamath.

Final Answer:
The book "Colours of the Rainbow" was written by A. V. Kamath, making that the correct answer.