Which one of the following sets of elements was primarily responsible for the origin of life on the Earth?

The origin of life on Earth is fundamentally linked to the elements Carbon, Hydrogen, and Nitrogen. These elements, along with Oxygen, Phosphorus, and Sulfur (collectively known as CHNOPS), constitute approximately 98% of all living matter [3]. Carbon serves as the versatile backbone for all organic molecules due to its ability to form stable covalent bonds and complex structures [2]. Hydrogen is the most abundant element in the universe and a primary component of water and hydrocarbons. Nitrogen is essential for the formation of amino acids, which are the building blocks of proteins, as well as the nitrogenous bases in DNA and RNA [2]. While Oxygen is abundant, the primordial atmosphere was likely a reducing environment where elements were bonded to Hydrogen (as methane and ammonia) before free oxygen became prevalent. Other elements like Sodium, Potassium, and Calcium are vital nutrients but were not the primary structural elements for the initial organic synthesis [1].

Sources

1. [2] https://www.nhm.ac.uk/discover/eight-ingredients-life-in-space.html
2. [3] Environment, Shankar IAS Acedemy .(ed 10th) > Chapter 2: Functions of an Ecosystem > 2.7. BIO.GEO-CHEMICAL CYCLE > p. 17
3. [1] Environment and Ecology, Majid Hussain (Access publishing 3rd ed.) > Chapter 1: BASIC CONCEPTS OF ENVIRONMENT AND ECOLOGY > Carbon and Oxygen Cycles > p. 19