Answer : 3. "Universal Serial Bus"
Explanation :

1. The full form of USB is Universal Serial Bus.

2. USB is a wired device with the help of which you can connect any other device like mobile with laptop, mobile with computer etc.

3. Apart from this, you can also insert a memory card inside the laptop with its help because it is a port in which we can insert things like Pendrive, Card Reader, Data Cable etc.