what type of sensors does the Boeing 737 MAX use for MCAS?
The pitot tube has nothing to do with the angle of attack. It is used for measuring pressure which in turn gives you the airspeed.

Accelerometers are used for the Inertial Navigation System.

The angle of attack is another sensor (shown below): the principle is that it rotates and reads the angle between the current position and the reference position.



Regarding the 737 MAX, there are two AoA sensors one on the captain side and one on the first officer side.

The MCAS reads the AoA from the captain side.