Which two peninsulas form part of the coast of mexico

The answer is - Baja California and Yucatan.

Baja California occupies the northwestern coast of Mexico. It is like a long thin line stretching in front of the mainland Mexico. This peninsula has harsh arid climate and it's very hot, but the water is colder and there's also nice long beaches that are very attractive as a weekend and tourist destination for the US citizens that live in the western part of the US.

Yucatan occupies part of the eastern coast of Mexico. It has a more oval shape and is covered with dense tropical rainforest. This peninsula is well know for two things:

1. The magnificent archeological sites of the Central American civilizations like the Aztec, Maya, Olmec, Toltec.

2. This is the place where it is thought that along its shores the meteorite that wiped out the dinosaurs had fallen.

a and b because with the other three, they simplify to something else.