In which one of the following animals do distinct black stripes extend from the inner corners of the eyes to the mouth?

In human body, which one of the following synthesizes cholesterol?

If the drinking water supply pipeline is damaged and is contaminated with water from domestic sewerage, which one of the following diseases is most likely to occur after drinking such water?

Which one of the following is not a part of small intestine?

Under which of the following conditions can the President of India proclaim Emergency?

1. Failure of the constitutional machinery of the State
2. Occurence of large scale natural calamities or epidemics
3. Threat to the financial stability of the country

Select the correct answer using the codes given below:

Consider the following :

1. Cotton
2. Silk
3. Wool

Which of the above contains/contain nitrogen in its structure?