Final answer:
Electronegativity decreases from top to bottom within a group on the periodic table due to increased atomic size, meaning Option 2: Decreases is the correct answer to the question.
Step-by-step explanation:
The electronegativity of an element is its tendency to attract electrons when it forms a compound. Within the periodic table, electronegativity values exhibit certain trends. Electronegativity commonly decreases from the top to bottom of a group on the periodic table. This decrease is attributed to the increase in atomic size as one moves down a group, which results in the outermost electrons being farther away from the nucleus and, therefore, less strongly attracted.
Conversely, electronegativity tends to increase from left to right across a period. This increase is due to the atomic size generally decreasing within a period as more protons are added to the nucleus, thus enhancing its ability to attract bonding electrons.
Therefore, in response to the question, the correct option is Option 2: Decreases. Electronegativity decreases from top to bottom within a group on the periodic table. For example, in the halogen group, fluorine has the highest electronegativity, and the value decreases as you go to chlorine, bromine, and iodine respectively.