Sugarcane shows high efficiency of CO2 fixation because it performs

Explanation

RUBISCO which is most abundant enzyme in world can bind to both `CO_2` and `O_2` on its active sites. RUBISCO has much greater affinity for `CO_2` than `O_2` This binding is competitive. It is the relative concentration of `O_2` and `CO_2` which determines which of the two will bind the enzyme. In `C_4` plants photorespiration does not take place. Such plants bear a mechanism due to which `CO_2` concentration at enzyme site increases. This is due to splitting of `C_4` acid in mesophyll leading to release of `CO_2` thereby increasing the concentration of `CO_2`. This increases the carboxylase activity of RUBISCO and decreases the oxygenase activity.