Libraries run by charitable trusts are an example of:

The correct option is Not for profit organisation.

Here is a step-by-step breakdown of why libraries run by charitable trusts are classified as not-for-profit organisations:
1. Primary Motive: The fundamental goal of a charitable trust is to provide public benefit, promote education, and support community welfare. Libraries operated by these trusts exist to spread knowledge and facilitate learning, rather than to earn profits for private owners.
2. Financial Structure: Any income these libraries generate, whether through voluntary donations, government grants, or nominal membership fees, is strictly used to maintain the library, purchase new books, and pay for operational costs. Unlike commercial businesses, no surplus funds are distributed to trustees or founders.
3. Comparison with Other Options:
- Partnership: A relationship between two or more individuals who agree to share the profits and losses of a business run by them.
- Companies: Commercial entities formed to carry out business activities with the primary objective of earning profits for their shareholders.
- Cooperatives: Voluntary associations of persons who join together to promote their shared economic interests, which operate on mutual self-help rather than purely charitable public service.
Because libraries run by charitable trusts are dedicated entirely to community welfare without any profit-sharing motive, they are classified as not-for-profit organisations.