Final answer:
Dysprosium (Dy) is the metal that belongs to the lanthanide series from the given options, known for its magnetic and catalytic properties.
Step-by-step explanation:
The metal from the lanthanide series given the options is dysprosium (Dy). The lanthanide series contains fifteen metallic elements from cerium (Ce) to lutetium (Lu), and dysprosium falls within this series. The other elements listed such as rutherfordium (Rf), americium (Am), and mendelevium (Md) are not part of the lanthanide series. Rutherfordium is a transition metal that belongs to the fourth transition series, while americium and mendelevium are part of the actinide series, which is another set of inner transition metals. The lanthanide series elements are known for their magnetic, catalytic and phosphorescent properties.