The elements which occupy their positions is periodic table just after the members of zero group are:
(A) Metals
(B) Gases
(C) Radioactive
(D) Alkali metals

Hint :To answer this question, we first need to understand what a periodic table is. The periodic table, commonly known as the periodic table of elements, is a tabular representation of chemical elements organized by atomic number, electron configuration, and recurrent chemical properties. The table's structure reveals periodic patterns.

Complete Step By Step Answer:
Elements - An element is a pure substance made up entirely of atoms with the same number of protons in their atomic nuclei, as defined by chemistry. Chemical elements, unlike chemical compounds, cannot be broken down chemically into simpler molecules.
Group zero - Under normal conditions, noble gases are colorless, odorless, tasteless, and nonflammable. They were originally referred to as group 0 in the periodic table because their valence was thought to be zero, implying that their atoms could not mix with those of other elements to form compounds.
The elements are organized in seven horizontal rows, from left to right and top to bottom, in order of increasing atomic number. Periods are the rows, and they are numbered 1 through 7.
The elements that occupy their position just after the zero group are alkali metals.
So, the final answer is option (D) i.e., Alkali metals.

Note :
Periodic trends are distinct patterns in the properties of chemical elements that can be found in the periodic table. Electronegativity, ionization energy, electron affinity, atomic radii, ionic radius, metallic character, and chemical reactivity are all major periodic patterns.