Correct answer: you must pay constant attention to the road and its surroundings.

To anticipate a hazard, you need to see it in time, so keep your attention on the road and its surroundings at all times. Look far ahead, to the sides, and in your mirrors. In the image, the mirror shows a car behind you, and on the right, a cyclist is riding in the bike lane. If you focus only on the car ahead, you miss all of that.

Real Decreto 1428/2003, de 21 de noviembre, por el que se aprueba el Reglamento General de Circulación · Cuestiones de Seguridad Vial. Manual II