Final answer:
The left-turn signal hand sign consists of extending the left arm straight out to the side at shoulder height with the palm facing forward, to indicate the intention to turn left.
Step-by-step explanation:
The left-turn signal hand sign is crucial for cyclists to know and use when making turns on the road if their bicycle is not equipped with signal lights. When a cyclist is preparing to make a left turn, they should extend their left arm straight out to the side, with their palm facing forward, so that it's clearly visible to other road users. The arm should be at shoulder height and point in the direction of the turn, which is straight out to the left. This hand signal is recognized universally among motorists and cyclists, ensuring communication of the cyclist's intentions and contributing to road safety.