Statement (I): In a bipolar junction transistor increase in the collector voltage increases the base width.

Statement (II): Increase in the collector voltage increases the space-charge-width at the output junction diode.

When the collector voltage is increased then there is a decrease in the width of the base and this effect is known as an early effect.(Statement (I) is false)

Due to maintaining the charge neutrality, the penetration of the depletion region or transition region into the base width reduces and space charge width at the output junction diode increases (Statement (II) is True)

Statement (I) is false but Statement (II) is true.

Base-narrowing has two consequences that affect the current:

1) There is a lesser chance for recombination within the "smaller" base region.

2) The charge gradient is increased across the base, and consequently, the current of minority carriers injected across the collector-base junction increases, which net current is{\displaystyle I_{CB0}} called ICBO.

The characteristics are shown below: