With reference to the food chains in ecosystems, which of the following kinds of organism is / are known as decomposer organism/organisms?
1. Virus
2. Fungi
3. Bacteria

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Consider the following minerals
1. Calcium
2. Iron
3. Sodium

Which of the minerals given above is/are required by human body for the contraction of muscles?

Photochemical smog is a resultant of the reaction among

Which of the following statements is/are applicable to Jain doctrine?

1. The surest way of annihilating Karma is to practice penance.
2. Every object, even the smallest particle has a soul.
3. Karma is the bane of the soul and must be ended. 

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Which of the following diseases can be transmitted from one person to another through tattooing?

1. Chikungunya 
2. Hepatitis B 
3. HIV-AIDS

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Which of the following adds / add nitrogen to the soil?
1. Excretion of urea by animals
2. Burning of coal by man
3. Death of vegetation

Select the correct answer using the codes given below.