Which of these elements is a metal?

The options are missing, so I will answer the question in a general manner.

This group of elements includes the alkali metals, alkaline earth metals, transition metals, basic metals, lanthanides and actinides. Depending on conditions, elements belonging to the metalloid group may behave like metals. So, if you want to know if an element is a metal, just found it in the periodic table.

When bonding with nonmetals in ionic compounds, they are converted into cations. When bonding together they make metallic compounds. When multiple metals bound they form alloys (these can include nonmetals too).

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