Which of the following diagram represent the semiconductor behaviour? 

Explanation:

In a solid, the energy of electrons lie within certain range. The energy levels of allowed energy are in the form of bands, these bands are separated by regions of forbidden energy called band gaps.

The energy required for electrons and holes to transition from the valence band to the conduction band is called a band gap.

• Band Gap for \(Si=1.12eV\cdot\)
• Band Gap for \(Ge=0.67eV\cdot\)

The relationship between band gap energy and temperature can be described by Varshni's empirical expression:

• \(E_g(T)=E_g(0)-\frac{\alpha T^2}{T+\beta}\)

In semiconductors, the band gap between the valence band and the conduction band is \(E_g<3eV\). 

As the temperature of the semiconducting material increases, more electron hole pairs becomes available in the conduction band and valence band, and hence the conductivity increases or the resistivity decreases.

So, the correct answer is Option-1.