After an oil spill, bacteria that can metabolize hydrocarbons are released for bioremediation. After a month, two areas affected by the spill show different levels of improvement. Which factor should be measured to determine the difference in effectiveness between the two sites?

The presence of enzyme hydrocarbonoclastic in the bacteria cleans the mess of oil spill, the different results of the site can be by the action performed by them.

Explanation:

Bioremediation is the process of waste management by cleaning up the contamination by breaking them into nutrients and organic salts by bacteria.

The oil degrading bacteria has enzymes that cleans the oil contaminant in environmental friendly way.

The bacteria named Alcanivorax borkumensis feeds on hydrocarbon. The levels of improvement depend upon the presence of these bacteria and their action on the site.

The cleaner area will show their presence and contaminated will show their absence. So their concentration determine the  state of cleanliness after oil spill.

the correct answer is 2 and 4