Which of the following statements is/are correct?

Which of the following pairs shows a diagonal relationship?

What is the basic difference between the terms electron gain enthalpy and electronegativity?

The ionisation enthalpies of elements of the second period are given below: Ionisation enthalpy / $kcal \, mol^{-1}$: $520, 899, 801, 1086, 1402, 1314, 1681, 2080$. Match the correct enthalpy with the elements and complete the graph given in Fig. Also,write the symbols of the elements with their atomic numbers.

The incorrect order of properties for the following is:

Choose the correct option regarding the following statements:
Statement-$1$: Nitrogen has lesser electron gain enthalpy than oxygen.
Statement-$2$: Oxygen has lesser ionization enthalpy than nitrogen.