Why are c4 plants able to photosynthesize with no apparent photorespiration?

The question is incomplete as it does not have the answer which are:

A) They do not participate in the Calvin cycle.

B) They use PEP carboxylase to initially fix CO2.

C) They conserve water more efficiently.

D) They exclude oxygen from their tissues.

They use PEP carboxylase to initially fix CO2.

Explanation:

Photorespiration is a wasteful process in plants which produces less amount of ATP and low glucose level as the RUBISCO enzyme binds with the oxygen instead of Carbon dioxide.

The Rubisco enzyme binds with the carbon dioxide usually during the Calvin cycle but in hot and dry conditions it binds the oxygen.

So to avoid the photorespiration, plants evolved adaptive features in the anatomy of the leaf that is they separated the photosynthetic steps by forming wreath-like structure around the vascular bundles called Kranz anatomy.

Instead of Rubisco, PEP carboxylase binds the carbon dioxide, convert it to malate and then transport it to bundle sheath cell where the Calvin cycle takes place as malate provide Carbon dioxide gas to Rubisco enzyme.

Thus, the selected option is correct.

the food storage products of chrysophytes are oils or the polysaccharide laminarin.   formerly classified as plants, the chrysophytes contain the photosynthetic pigments chlorophyll a and c all but the yellow-green algae also contain the carotenoid pigment fucoxanthin.