The two types of bonds present in $B_2{H}_6$ are covalent and :

The chemical in question, ${\mathrm{B}}_2{\mathrm{H}}_6$, has the following structural features:

From this image, we can deduce the following information: -There are four hydrogen atoms in the terminal position. The terminal B-H bond is shorter than the bridge B-H bond in length. This proves that bridge B-H bonds are stronger than terminal B-H bonds. -

According to the Molecular Orbital Theory, the bonds between the boron atoms and the terminal hydrogen atoms are typical 2-centre, 2-electron covalent bonds. However, the bridges' bonding between the boron and hydrogen atoms is different from that of substances like hydrocarbons.

The boron atom has one additional electron available for future chemical connections after using two electrons to create a bind with the terminal hydrogen atoms. The hydrogen atoms are currently acting as a bridge by lending one electron apiece. The ${\mathrm{B}}_2{\mathrm{H}}_6$ ring is held together by four electrons from two 3-center 2-electron bonds that they are creating. The term "banana bond" is often used to describe this form of interaction.

Banana bonds, also known as hydrogen bridge bonds, are another name for them.  thus has both covalent and hydrogen bridge bonds.
So, C is the best choice.