ser is the correct I think
With expressions such as 'es raro que' you need to use the subjunctive form of a verb which is slightly different than the present, indicative form. So, the 'normal' form of ir for third person plural would be van. However, we need the subjunctive form here, which is vayan.
This means that the correct answer is A. Vayan a la escuela los sabados.
The form ven doesn't exist.
Answer:
1 question: The hair clipper adapts perfectly to the shape of your head without any Errors
