Is the word in bold a British or an American spelling?

1. I prefer the flavor of vanilla ice cream to chocolate. American British
2. The recipe calls for one liter of water. American British
3. I received a catalogue in the mail for the latest fashion trends. American British
4. The new building was modelled after an old castle. American British
5. The army was ready for defense against the enemy. American British
6. She put on a pretence of happiness when really she was feeling sad. American British
7. The carpenter leveled the shelves before attaching them to the wall. American British
8. The paediatrician examined the newborn baby. American British
9. I wrote a cheque for the rent payment. American British
10. The venom of the spider can paralyze its prey. American British
11. The wedding was held in a beautiful garden, surrounded by the splendour of nature. American British
12. The addition of a catalyst can catalyze a chemical reaction. American British
13. After a few years, I started to realize the importance of education. American British
14. The project required a great deal of rigor and attention to detail. American British
15. The farmer ploughed the soil. American British
16. She wore her favorite piece of jewelry to the party. American British
17. Aluminium is a lightweight and durable metal. American British
18. The chemist worked to synthesise a new compound. American British
19. The soldier showed great valour in the face of danger. American British
20. Estrogen is a hormone that plays an important role in the female reproductive system. American British