The correct option is B 1, 4
Biodegradable wastes are those which are easily decomposed by microbes. It mainly consists of organic wastes like kitchen waste, cattle dung, plant parts etc. Good quality fuel can be extracted from well decomposed waste. Many bio-fuel projects have been started in cities. Biodegradable wastes are This waste is mainly of organic type and is also called ‘wet solid waste’ or ‘wet
garbage’.