Hello!
The correct answer is:
En los EE.UU. cada abril se permite tener niños en el trabajo por un día.
Why?
According to the impersonal se formula:
se + verb in third person singular
Our verb is "permitir" which conjugated in the third person singular is "permite"
We are allowed to use four words including the verb so, the words that would match with this sentence are:
"se permite tener niños"
Translated sentence:
In the U.S. every April is allowed to bring kids to work for a day.
Take Our Daughters and Sons to Work Day is a national day when it's allowed to bring kids to work for a day to show them the working world.
Have a nice day!