Answer:
The correct answer is small coins that provide energy
Step-by-step explanation:
Small coins structures are found in chloroplast which are termed as thylakoid.There are stacks like arrangement of thylakoids within the granum.
The Surface area of thylakoids is being increased by grana as a result more light is absorbed by the chloroplast.
The thylakoid of granum is the site of light reaction.