The mouse wont connect to the usb port. the mouse works on the port before, until a sudden lose power occurred and i start the computer again. i start the computer and the mouse is not working anymore, but usbs, hardisks and phone connections work on that same port. but when i reconnect the mouse, it still wont work, how do i fix this?

Try replacing the batteries inside the mouse. If it still doesn't work, check external appliances on the computer, as it may not have read it on there ( external appliances & mouse).
If you still can't fix it, it is better to get a tech person's help.

i guess the correct option is letter a.

use contrasting font sizes, but the same font style