In c4 plants such as corn and sugarcane, carbon fixation takes place in the cells, and then the co2 is transferred as malic or aspartic acid to cells where carbon dioxide is released for entry into the calvin cycle.

Mesophyll and bundle sheath cell.

Explanation:

C4 pathway is also known as hatch slack pathway it is a photosynthetic process in some plants. In this pathway carbon is extracting from carbon dioxide to able to use in sugar and other biomolecules. C4 is known as four carbon molecules which is the 1st product of this type of carbon fixation.

In this pathway rubisco enzyme works in the environment where lots of carbon dioxide and very little oxygen present. CO2 is transferred via malate or aspartate from mesophyll cells to bundle sheath cells. In bundle sheath cell CO2 is released by malate decarboxylation.

C4 plants use PEP carboxylase to absorb more amount of CO2 in the mesophyll cells. Phosphophenolpyruvate (PEP) which is 3 carbon molecule binds with CO2 and make oxaloacetic acid, it forms than malate, 4carbon molecule. Malate enters through a plasmodesmata into bundle sheath cell and release the CO2.

your answer should be c) enjoy!