Lanthanoids like Eu and Yb can form hydrides like EuH₂ and YbH₂. These hydrides are

ionic hydrides

The correct answer is (1) ionic hydrides, then the hydrides of lanthanoids like EuH₂ and YbH₂ are considered to be ionic hydrides.

In ionic hydrides, the lanthanoid atom (Eu or Yb) donates electrons to the hydrogen atom, resulting in the formation of positively charged lanthanoid ions (Eu²⁺ or Yb²⁺) and negatively charged hydride ions (H^-). This ionic bonding arises from the large difference in electronegativity between the lanthanoid atom and hydrogen.