A hydraulic fuse is designed to:

Automatically shut off flow if a line downstream ruptures, preserving system pressure

Correct

Filter the hydraulic fluid

Regulate system pressure

Cool the hydraulic fluid

Explanation

A hydraulic fuse detects abnormally high flow (indicating a leak) and shuts off supply to that line to preserve fluid and pressure.

Test yourself with random questions from Aircraft General Knowledge and all other ATPL subjects.