Alkyl halides are considered to be very reactive compounds towards nucleophiles because:

Explanation

Alkyl halides are considered to be very reactive compounds towards nucleophiles because they have an electrophilic carbon and a good leaving group.The carbon atom in an alkyl halide is electrophilic because it has a partial positive charge due to the difference in electronegativity between carbon and the halogen atom. This makes the carbon atom a good target for nucleophiles, which are molecules or ions that have a pair of electrons that they can donate to form a new bond.The halogen atom in an alkyl halide is a good leaving group because it is relatively stable and it can easily leave the molecule. This is because the halogen atom has a high electronegativity, which means that it can easily attract electrons from other atoms.The combination of an electrophilic carbon and a good leaving group makes alkyl halides very reactive towards nucleophiles. When a nucleophile attacks an alkyl halide, the nucleophile donates its electrons to the carbon atom, displacing the halogen atom. This forms a new bond between the nucleophile and the carbon atom, and the halogen atom leaves as a leaving group. Therefore, option b is correct.