Which set of curved arrows accounts for the deprotonation of an acid (A-H) by a base (:B)?

What base is formed in the following acid-base reaction?

Bonus question Histidine an amino acid has the following structure. Rank the indicated protons in order of increasing acidity.

The sigma bond that is part of C=N in the following compound results from the overlap of which orbitals?

Which one of the following mechanistically depicts the protonation of methanol by hydrogen bromide?

Identify from the options given the proper curved arrow to convert the first resonance structure into the second resonance structure.

Identify the conjugate base of the compound shown in the box below.

What is the role of methylchloride (CH3Cl) in the following reaction? 

What is the ground-state electronic configuration of a sodium cation?

Tamiflu®, the most effective antiviral drug used to treat avian influenza, has the following structure. Identify the indicated functional groups in Tamiflu®.