- A protractor is a kind of tool
- A protractor is used for measuring the angles of a triangular object
- So, a protractor is the best tool to measure the angles of a triangular object

So, a protractor is the best tool to measure the angles of a triangular object
Which is the best tool to measure the angles of a triangular object?
- A protractor is a kind of tool 
- A protractor is used for measuring the angles of a triangular object