The correct answer is option 1. Be, Mg, and Ca is the correct order arranged in increasing atomic radius. This is predicted based on the periodic table. The atomic sizes increases as one moves downwards in the periodic table.
Answer:
<h2>
total no. of electron present in Valency shell is called valency electron </h2><h2>___________________</h2>
<h2>valency shell is that in which last electron is present</h2>