One of these is not singular. Identify it:

Correct option is B

The correct answer is (b) Data because it is not singular.

Explanation of correct answer in minimum 2 lines:

While “data” is often used as an uncountable singular noun in everyday modern English, it is technically a plural form of the Latin word “datum”. In formal contexts, it still retains its plural usage, especially in scientific or academic writing.

In Hindi: “Data” तकनीकी रूप से “datum” का बहुवचन है, और यह एकवचन नहीं है।

Example:

• Formal: The data have been analyzed.
• Informal: The data is reliable.

Explain why other options are incorrect:

▪ (a) Book

English Meaning: A single bound set of written or printed pages.

Hindi Meaning: किताब — यह स्पष्ट रूप से एकवचन है।

▪ (c) Economics

English Meaning: The branch of knowledge concerned with production and consumption of goods and services. Though it ends with –s, it is a singular uncountable noun.

Hindi Meaning: अर्थशास्त्र — यह एकवचन विषय है, जैसे Mathematics, Physics।

▪ (d) Mouse

English Meaning: A small rodent or a computer input device.

Hindi Meaning: चूहा — यह एकवचन है। इसका बहुवचन होता है