Arrange the following major elements present in the Earth's crust, in ascending order, in weight percentage : 1. Aluminium 2. Calcium 3. Silicon 4. Oxygen Select the answer using the code given below :

The Earth's crust is composed of several major elements, with oxygen being the most abundant by weight at approximately 46.6% [1]. Silicon follows as the second most abundant element, making up about 27.7% of the crust's mass [1]. Aluminium is the third most abundant element and the most common metal, accounting for roughly 8.1% to 8.3% [1]. Calcium is found in smaller proportions, representing approximately 3.6% to 4.2% of the crustal weight [1]. To arrange these elements in ascending order (from least to most abundant by weight percentage), the sequence is Calcium (3.6%), Aluminium (8.1%), Silicon (27.7%), and Oxygen (46.6%). This corresponds to the sequence 2, 1, 3, 4 as provided in the options.

Sources

1. [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 4: Earths Interior > The Crust > p. 53