What should a Green Card holder who moved from Texas to California in May answer in "Your State of Domicile"?

I moved from Texas to California in May. I bought a house in California in December. I am Green Card holder.
What should be the answer for "Your state of Domicile"?

The question is "Where were you domiciled?"
I still hold passport of a foreign country but a green card of USA.
If I should select "In the United States" then should California be the "State of Domicile" because for the foreseeable future, this is where I am going to live?