The elements in which s and p orbitals are present
A. Common elements
B. Inert gases
C. Halogens
D. Transition elements

Hint: Elements are arranged in a tabular form called periodic table and there are 115 elements present in the periodic table. There are similarities as well as differences in the properties of these elements. On the basis of these properties elements can be divided into metals and non-metals.

Complete answer:
Metals are arranged on the left side of the periodic table and there are five kinds of metals: Alkaline earth metals, Alkali metals, Transition metals, Actinides and Lanthanides.
Modern periodic table given by Mandeleev consists of 18 vertical columns known as groups arranged as left to right and seven horizontal rows known as periods arranged from top to bottom. In this periodic table elements are arranged according to their atomic number and this table divides the elements into s, p, d and f-block elements on the basis of their valence shell electrons. The elements which are present in s and p block are known as common elements, d block elements are transition elements whereas f block elements are inner transition elements. Here inert gases are those which have fully filled atomic orbital while halogen are very reactive compounds having one less electron in their outermost shell.

Thus, option A is the correct answer.

Note:
Atomic size is defined as the distance between the center of nucleus of an atom and its outermost shell. Where an atom consists of a nucleus which is made up of protons and neutrons and electrons are revolving around the nucleus.