Which of the following is/are the advantages of solar cells?

All of the above

Solar cells have no moving parts so there is less energy wasted in the forms of heat or sound or frictional forces. This helps in increasing its efficiency.
Since there is no moving part in solar cells there is no physical damage done to the equipment and once after setup cells are just kept under the sky and require minimum maintenance.
There is absolutely no other raw materials or high machinery system required, such as fuels, or turbine generators. All they need is just the Sun to provide solar energy, and hence they can be set up anywhere under the sky, in remote areas too.