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Because $H-F$ bonding $>H-C l\,>\,H-B r$ [Strength of hydrogen bond]
Highest the hydrogen bonding point highest the boiling point.
$(A) \,2p_y +2p_y \to \pi-$ બંધ રચના
$(B) \,2p_x + 2p_x \to \sigma-$ બંધ રચના
$(C)\, 3d_{xy} + 3dp_{xy} \to \pi$ -બંધ રચના
$(D)\, 2s + 2p_y \to \pi-$ બંધ રચના
$(E)\, 3d_{xy} + 3d_{xy} \to \delta -$ બંધ રચના
$(F)\, 2p_s + 2p_s \to \sigma-$ બંધ રચના