Refer to figure.
EASA learning objective 022.02.01.02.07 states:'Describe a modern pitot static system using solid-state sensors near the pitot probe or static port converting the air data to numerical data (electrical signals) before being sent to the air-data computer(s).'

The figure in the question shows a primary flight display (PFD)which is an electronic display screen which replaces the conventional primary flight instruments. Although a PFD displays altitude, the actual calculation of altitude and other air data is carried out by an Air Data Computer (ADC) before being fed to the PFD. In modern civil air transport aircraft the ADC is usually incorporated in the inertial reference unit and called an air data inertial reference unit (ADIRU)

Altitude calculation is based on the measurement of atmospheric static pressure which reduces with altitude.

In a conventional mechanical altimeter static pressure is fed to the instrument via a pipeline from the static port. An aneroid capsule inside the instrument, connected to the display pointers, expands and contracts with changes in static pressure.

An Air Data Computer needs a static pressure input to be able to calculate altitude but this needs to be a digital input. This is acheived by using an Air Data Module (ADM) which contains solid state pressure transducers which convert the pressure from the static port into a digital signal that the ADC/ADIRU can use. The ADC/ADIRU then feeds that information to the PFD and any other systems that require it.

Regarding the altimeter display shown in the annex, the input pressure source is...

calculated within the instrument, in analogue form, by subtracting static pressure from pitot pressure --> INCORRECT. The PFD receives digital information from the ADC, altitude is sensed by measuring static pressure only.

static, and it is converted into a digital signal by a transducer --> CORRECT. Altitude is calculated by sensing static pressure. The static port connects to an air data module containing a transducer which outputs a digital signal to the ADC.

static, and it is transmitted from the source to the instrument through a pipeline --> INCORRECT. There is no pipeline from the static port to the PFD.

calculated by the Air Data Computer by subtracting static pressure from pitot pressure --> INCORRECT. Static pressure is fed directly to an ADM from the static port then to the ADC, pitot pressure is irrelevant.