Answer:
As I think second option is the correct one.
Explanation:
The myofibrils are made up of thick and thin myofilaments, which help give the muscle its striped appearance. The thick filaments are composed of myosin, and the thin filaments are predominantly actin, along with two other muscle proteins, tropomyosin and troponin.
I'd say Solar energy is a source we humans could use in the future
Look up the symbol that it is pointing to and the name should pop up