The increasing order of reactivity of the following compounds towards reaction with alkyl halides directly is

(A)

(B)

(C)

(D)

The major product of the following reaction is

In a chemical reaction,


the initial concentration of B was 1.5 times of the concentration of A, but the equilibrium concentrations of A and B were found to be equal. The equilibrium constant (K) for the aforesaid chemical reaction is -

Mn₂(CO)₁₀ is an organometallic compound due to the presence of -