From: Steve Shaw - PM
Date: 13 Oct 17 - 11:28 AM
"Do you want Catalonia to become an independent state in the form of a republic?"
That is a leading question by any measure. Try this:
What options would the two boxes give?
Your wording of the question precludes a simple yes/no answer, so it
“There is an opportunity for Catalonia either to remain a part of Spain or to become an independent state in the form of a republic. Please state your preference by ticking one of the two boxes below...”
also risks that the two options against the boxes will also be subject to bias.

You need to think these things through a little before posting you suggestions.