Concept:
Ancient India made remarkable contributions to mathematics and science. One of the greatest discoveries in world mathematical history was the concept of zero.
Indian mathematicians developed:
• decimal notation,
• place value system,
• and the use of zero as a number.
This contribution later spread to different parts of the world.
Step 1: Understanding Assertion (A).
Assertion (A) states:
\[
\text{Ancient Indians discovered the concept of zero about the second century BCE.}
\]
This statement is generally accepted as correct in the context of ancient Indian mathematical development.
Indian mathematical traditions gradually evolved the use of:
• zero,
• positional notation,
• and decimal calculations.
These developments became foundational for modern mathematics.
Step 2: Understanding Reason (R).
Reason (R) states:
\[
\text{The Arabs learnt and adopted it from India and spread it in Europe.}
\]
This statement is also correct.
Arab scholars:
• studied Indian mathematical systems,
• adopted Indian numerals,
• and transmitted mathematical knowledge to Europe.
As a result, the Hindu-Arabic numeral system became globally influential.
Step 3: Evaluating the relationship between Assertion and Reason.
Although both statements are correct, the Reason does not directly explain why ancient Indians discovered zero.
The Reason only explains:
• how the knowledge spread,
• not the actual cause or basis of the discovery.
Therefore:
• Assertion (A) is correct,
• Reason (R) is correct,
• but Reason (R) is not the correct explanation of Assertion (A).
Step 4: Historical importance of zero.
The invention of zero transformed mathematics because it:
• simplified calculations,
• enabled algebraic development,
• and strengthened scientific progress.
Without zero, modern mathematics and computer science would not have developed in the same way.
Step 5: Final conclusion.
Since both statements are correct but the Reason does not explain the Assertion, the correct answer is:
\[
\boxed{\text{Both (A) and (R) are correct but (R) is not the correct explanation of (A)}}
\]