Intramolecular H−bonding is present in ortho-nitrophenol. This compound contains a hydroxyl group (OH) and a nitro group (-NO2). The hydrogen in the hydroxyl group can form hydrogen bonds with other molecules.
So, the correct option is (A): o-nitrophenol
From the given following (A to D) cyclic structures, those which will not react with Tollen's reagent are : 
Compound 'P' undergoes the following sequence of reactions : (i) NH₃ (ii) $\Delta$ $\rightarrow$ Q (i) KOH, Br₂ (ii) CHCl₃, KOH (alc), $\Delta$ $\rightarrow$ NC-CH₃. 'P' is : 

The formal charges on the atoms marked as (1) to (4) in the Lewis representation of \( \mathrm{HNO_3} \) molecule respectively are 
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.