(a) 1 %

(b) 5 %

(c) 8 %

(d) 10 %

Correct option – ( a )

Explanation for correct option – plants prepare there food in the presence of sunlight and chlorophyll and water . Photosynthetically active radiation which is trapped by the plants in synthesis  of organic matter is approximately 1 – 2 % of incident solar energy

Hence correct option is 1 %