Direction: In the following passage there are blanks, each of which has been numbered. Choose the correct word from the given options which fits the blank appropriately.

Solar energy is considered one of the most important ____(1)____ energy sources, which is ____(2)____. Solar energy plays a huge role in the ____(3)____ to renewable energy, but there's a catch — recycling solar panels is ____(4)____ easy nor profitable. ____(5)____ a solution to recycle the panels is the need of the hour to prevent a solar trash wave.