You are at an intersection where the traffic lights are working, so the “Give way” sign (2.4) is not taken into account (clause 173). The traffic light shows you a green signal, and the indicator on your dashboard shows that you intend to turn left. When turning left on a green signal, you are required to give way to the oncoming bus going straight (clause 90). The yellow flashing beacon of the truck on the right (yellow beacon) only warns of danger and gives no priority in traffic (clause 32). Besides, since your light is green, the truck has a prohibiting red signal, so there is no need to give way to it.
Option 1. The truck has no priority, because its yellow beacon gives no privilege and it has a red signal. Option 2. A yellow flashing beacon only warns of danger and never gives priority over other vehicles.
Give
green
yellow