Recently, "oilzapper" was in the news. What is it? .

Oilzapper is a bioremediation technology developed by CSIR-Indian Institute of Petroleum, Dehradun. It uses a consortium of indigenous hydrocarbon-degrading microbes that break down oily sludge and spilled crude into harmless by-products. It needs no harsh chemicals, so it is cheap and environmentally friendly. That makes option A correct.

Why the others are wrong:

• B is wrong. Oilzapper is not an exploration tool. It works on oil that has already been spilled or has accumulated as sludge.
• C is wrong. A genetically engineered maize for biofuel is a biotech crop, which has nothing to do with oil cleanup.
• D is wrong. Controlling blowouts and well fires uses capping, specialised fire-fighting and well-control engineering, not microbes.

Core concept: microbial bioremediation and sludge management. For Mains, this links to GS-III (environment, pollution control, indigenous S&T) and to the broader debate on cleaning up oil spills without secondary pollution.

Trap: aspirants see the word "zapper" and assume a physical or engineering device for fires or wells. Always check what the technology actually acts on.