The solar energy you are referring to refers to light kinetic energy. There are usually letters quartz on the quartz dial, which means quartz watch.
At present, light kinetic energy watches should only be sold by Citizen in Japan, and they will have light kinetic energy on them. The watch logo appears to be Ecology-Drive.
There are very few purely solar watches these days, the electronic watches I wore back then. I was a kid and had solar panels on them, like the ones on calculators.
A Because crystalline silicon is currently the most mature and widely used solar cell material, so A is correct ; the main material for manufacturing optical fiber is SiO 2, so B is correct; C. Because the main raw materials for making cement are limestone and clay, so C is false D.Because water glass is non-flammable and non-explosive; it can be used as a fire retardant for wood, so D is correct. Therefore, choice: C.