Biosparging is an in-Situ Bioremediation techniques in which we inject the air under pressure below the water table to enhance the rate of biological degradation of contaminants by naturally occurring bacteria. Hence statement 1 is right. In Google Scholar search engine is filled with academic papers on genetic engineering approaches to bioremediation. Hence 3 is also right. But not all compounds are susceptible to rapid and complete biodegradation, and bioremediation often takes longer time than other treatment processes. So, second statement unlikely to be correct. Hence, answer "C" 1 and 3 only.