Final answer:
Across the periodic table from left to right, the elements transition from metals to nonmetals. Metals possess conductive and malleable properties, while nonmetals are generally brittle and poor conductors. The correct answer to the question is option 2: metals to nonmetals.
Step-by-step explanation:
As we move across the periodic table from left to right, the elements transition from metals to nonmetals. This is due to the increase in the number of protons in the nucleus as the atomic number increases, which in turn attracts the valence electrons more strongly, making them less likely to be lost and more likely to be gained. Metallic character therefore decreases from left to right across a period. This transition is passed through metalloids, which exhibit properties intermediate between metals and nonmetals and are located along a diagonal band that separates the metals from the nonmetals.
Answering the student's question, option 2) metals to nonmetals is correct, as the elements change from having metallic properties, including being lustrous and good conductors of electricity, to possessing nonmetal characteristics, such as being poor conductors and often brittle when solid.