Strongest bond out of the following is -: (A) Electrostatic, (B) Hydrogen, (C) Hydrophobic, (D) Vanderwall's
Answer is A. Amongst the given options, electrostatic bonds are strongest. Strength of various interactions (in decreasing order)

Covalent (strongest) Electrostatic  (ionic or salt linkage) > hydrogen> hydrophobic > Van der waal's (weakest)