Extrinsic Semiconductor

The above are schematic diagrams of extrinsic semiconductors, into which doping agents of Boron(B) and phosphorus(P) have been introduced, respectively. Which of the following statements is correct?

a) Silicon(Si) has $4$ valence electrons.

b) Phosphorus(P) has $3$ valence electrons.

c) The above left are N-type semiconductors and the above right are P-type semiconductors.

d) Electrons are the majority charge carriers of the above right semiconductors, and holes are the majority charge carriers of the above left semiconductors.