In the context of solving pollution problems, what is/are the advantage/advantages of bioremediation technique ? 1. It is a technique for cleaning up pollution by enhancing the same biodegradation process that occurs in nature. 2. Any contaminant with heavy metals such as cadmium and lead can be readily and completely treated by bioremediation using microorganisms. 3. Genetic engineering can be used to create microorganisms specifically designed for bioremediation. Select the correct answer using the code given below:

1. Statement 1 is correct. Bioremediation utilizes biological agents, primarily microorganisms or their enzymes, to break down or remove pollutants. It works by enhancing the natural biodegradation process. 2. Statement 2 is incorrect. While bioremediation can be used to immobilize or transform certain heavy metals, it cannot completely degrade them as they are elements. The process is often not readily applicable to *any* contaminant with heavy metals like cadmium and lead for complete removal in the way organic pollutants might be treated. 3. Statement 3 is correct. Genetic engineering allows scientists to modify microorganisms to enhance their ability to degrade specific pollutants or survive in harsh conditions, thus creating microbes specifically designed for bioremediation tasks. 4. Therefore, statements 1 and 3 are correct.