Cyanobacteria have been engineered to produce isobutanol directly. what advantage does this have over other alternative biofuels?

a. it is an inherently renewable fuel source.
b. multiple processing steps can be avoided.
c. they produce chemical energy through photosynthesis.
d. they make a biofuel alternative to gasoline.

The answer is b.Multiple processing steps can be avoided.

Traditionally, energy crops are used for ethanol production thanks to yeast cultures. But, cyanobacteria can naturally ferment alcohol, such as isobutanol, without the need of yeast cultures. This way some steps are avoided and the process is faster. Also, cyanobacteria have a fast life cycle, so it can be produced great amounts of isobutanol for a short period of time.

oceans

indian ocean

pacific ocean

atlantic ocean

arctic ocean

southern ocean

it is either c or d and i know for sure it is not a or b