Match List - I with List- II. Choose the correct answer from the options given below:
| List - I (Hydrides) | List - II (Nature) | ||
| (a) | MgH2 | (i) | Electron precise |
| (b) | GrH4 | (ii) | Electron deficient |
| (c) | B2H6 | (iii) | Electron rich |
| (d) | HF | (iv) | Ionic |
To solve this matching problem, we need to correctly pair each hydride from List - I with its nature from List - II:
Based on these pairings, the correct match is:

Given below are two statements:
Statement I: Transfer RNAs and ribosomal RNA do not interact with mRNA.
Statement II: RNA interference (RNAi) takes place in all eukaryotic organisms as a method of cellular defence.
In the light of the above statements, choose the most appropriate answer from the options given below:
Such a group of atoms is called a molecule. Obviously, there must be some force that holds these constituent atoms together in the molecules. The attractive force which holds various constituents (atoms, ions, etc.) together in different chemical species is called a chemical bond.
There are 4 types of chemical bonds which are formed by atoms or molecules to yield compounds.