This Is a Certified Answer

Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
Electro negativity  X  =
       1/2 [  ionization enthalpy + electron gain enthalpy or affinity ]

X is higher => higher negativity.

Electronegativity is the property of molecule ,in the molecule to pull the electron towards an atom.and electron gain enthalpy is also the one type of electron pulling property . so higher electron gain enthalpy higher electronegativity .so atom B has higher electronegativity.