ANS:C - 4

NAND gate IC pin configuration shows a clear explanation of this question.

Ic 7400 contains 4 logic gates. It is a two-input and one output gate. NAND gate ic has 14 total pin.

Pin1,2,4,5,9,10,12,13 are input pins and pin 3,6,8,11 are the output pins whereas pin 7 is ground and pin 14 is connected to VCC(supply voltage +5v) on the bread board or trainer kit.