In this task, you are given a sentence. You must find the primary subject in the supplied sentence. The output must be a sub-sequence in the sentence.
One example is below.
Q: Rope and its Usage
A: Rope
Rationale: The word 'Rope' is the key subject here, while Usage is a property of Rope.
Q: The fibre selected, therefore, depends on the use for which the rope is intended.
A:
The fibre selected