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.

Q: As the rope is laid up its length contracts like a coiled spring, giving it a certain elasticity.

A: its length
****
Q: When new and untreated it is deep golden-brown in colour.

A: it
****
Q: A rogue's yarn is also used in commercially manufactured rope to indicate the type of fibre, its quality, and perhaps the particular manufacturer.

A:
A rogue's yarn
****