Almost everything that saves fuel also reduces risk, which is why the test asks about it.
Anticipate instead of braking
Every unnecessary braking event throws away fuel you have already burned to build that speed. Reading the road far enough ahead to lift off rather than brake is the single biggest saving available, and it also means you are never surprised.
Steady speed
On a motorway, hold a steady speed at or below the limit with a good gap ahead. The accelerate-brake cycle is what costs fuel. Following a truck closely to slipstream is both dangerous and illegal.
Tyres
Under-inflated tyres increase rolling resistance, so they cost fuel — and they also lengthen braking distances and wear out at the shoulders. Check pressures monthly when cold.
Weight and drag
Take unnecessary weight out of the car, and take the roof rack or box off when you are not using it. Aerodynamic drag rises with the square of speed, so a roof box costs far more at 120 km/h than at 50.
Idling
If you will be stationary for more than a minute or two, switch the engine off. Idling burns fuel for zero distance, and modern engines restart with negligible wear.
Disposal
Take used engine oil to a civic amenity site or a garage that accepts it. One litre contaminates an enormous volume of water, and disposal sites take it free of charge.